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1 /* | |
2 * Simplified by Andrey Novikov for AdBlock Plus | |
3 */ | |
4 | |
5 /* | |
6 * Licensed to the Apache Software Foundation (ASF) under one or more | |
7 * contributor license agreements. See the NOTICE file distributed with | |
8 * this work for additional information regarding copyright ownership. | |
9 * The ASF licenses this file to You under the Apache License, Version 2.0 | |
10 * (the "License"); you may not use this file except in compliance with | |
11 * the License. You may obtain a copy of the License at | |
12 * | |
13 * http://www.apache.org/licenses/LICENSE-2.0 | |
14 * | |
15 * Unless required by applicable law or agreed to in writing, software | |
16 * distributed under the License is distributed on an "AS IS" BASIS, | |
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
18 * See the License for the specific language governing permissions and | |
19 * limitations under the License. | |
20 */ | |
21 package org.apache.commons.lang; | |
22 | |
23 | |
24 /** | |
25 * <p>Operations on {@link java.lang.String} that are | |
26 * <code>null</code> safe.</p> | |
27 * <p/> | |
28 * <ul> | |
29 * <li><b>IsEmpty/IsBlank</b> | |
30 * - checks if a String contains text</li> | |
31 * <li><b>Trim/Strip</b> | |
32 * - removes leading and trailing whitespace</li> | |
33 * <li><b>Equals</b> | |
34 * - compares two strings null-safe</li> | |
35 * <li><b>startsWith</b> | |
36 * - check if a String starts with a prefix null-safe</li> | |
37 * <li><b>endsWith</b> | |
38 * - check if a String ends with a suffix null-safe</li> | |
39 * <li><b>IndexOf/LastIndexOf/Contains</b> | |
40 * - null-safe index-of checks | |
41 * <li><b>IndexOfAny/LastIndexOfAny/IndexOfAnyBut/LastIndexOfAnyBut</b> | |
42 * - index-of any of a set of Strings</li> | |
43 * <li><b>ContainsOnly/ContainsNone/ContainsAny</b> | |
44 * - does String contains only/none/any of these characters</li> | |
45 * <li><b>Substring/Left/Right/Mid</b> | |
46 * - null-safe substring extractions</li> | |
47 * <li><b>SubstringBefore/SubstringAfter/SubstringBetween</b> | |
48 * - substring extraction relative to other strings</li> | |
49 * <li><b>Split/Join</b> | |
50 * - splits a String into an array of substrings and vice versa</li> | |
51 * <li><b>Remove/Delete</b> | |
52 * - removes part of a String</li> | |
53 * <li><b>Replace/Overlay</b> | |
54 * - Searches a String and replaces one String with another</li> | |
55 * <li><b>Chomp/Chop</b> | |
56 * - removes the last part of a String</li> | |
57 * <li><b>LeftPad/RightPad/Center/Repeat</b> | |
58 * - pads a String</li> | |
59 * <li><b>UpperCase/LowerCase/SwapCase/Capitalize/Uncapitalize</b> | |
60 * - changes the case of a String</li> | |
61 * <li><b>CountMatches</b> | |
62 * - counts the number of occurrences of one String in another</li> | |
63 * <li><b>IsAlpha/IsNumeric/IsWhitespace/IsAsciiPrintable</b> | |
64 * - checks the characters in a String</li> | |
65 * <li><b>DefaultString</b> | |
66 * - protects against a null input String</li> | |
67 * <li><b>Reverse/ReverseDelimited</b> | |
68 * - reverses a String</li> | |
69 * <li><b>Abbreviate</b> | |
70 * - abbreviates a string using ellipsis</li> | |
71 * <li><b>Difference</b> | |
72 * - compares Strings and reports on their differences</li> | |
73 * <li><b>LevensteinDistance</b> | |
74 * - the number of changes needed to change one String into another</li> | |
75 * </ul> | |
76 * <p/> | |
77 * <p>The <code>StringUtils</code> class defines certain words related to | |
78 * String handling.</p> | |
79 * <p/> | |
80 * <ul> | |
81 * <li>null - <code>null</code></li> | |
82 * <li>empty - a zero-length string (<code>""</code>)</li> | |
83 * <li>space - the space character (<code>' '</code>, char 32)</li> | |
84 * <li>whitespace - the characters defined by {@link Character#isWhitespace(char
)}</li> | |
85 * <li>trim - the characters <= 32 as in {@link String#trim()}</li> | |
86 * </ul> | |
87 * <p/> | |
88 * <p><code>StringUtils</code> handles <code>null</code> input Strings quietly. | |
89 * That is to say that a <code>null</code> input will return <code>null</code>. | |
90 * Where a <code>boolean</code> or <code>int</code> is being returned | |
91 * details vary by method.</p> | |
92 * <p/> | |
93 * <p>A side effect of the <code>null</code> handling is that a | |
94 * <code>NullPointerException</code> should be considered a bug in | |
95 * <code>StringUtils</code> (except for deprecated methods).</p> | |
96 * <p/> | |
97 * <p>Methods in this class give sample code to explain their operation. | |
98 * The symbol <code>*</code> is used to indicate any input including <code>null<
/code>.</p> | |
99 * | |
100 * @author <a href="http://jakarta.apache.org/turbine/">Apache Jakarta Turbine</
a> | |
101 * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a> | |
102 * @author Daniel L. Rall | |
103 * @author <a href="mailto:gcoladonato@yahoo.com">Greg Coladonato</a> | |
104 * @author <a href="mailto:ed@apache.org">Ed Korthof</a> | |
105 * @author <a href="mailto:rand_mcneely@yahoo.com">Rand McNeely</a> | |
106 * @author Stephen Colebourne | |
107 * @author <a href="mailto:fredrik@westermarck.com">Fredrik Westermarck</a> | |
108 * @author Holger Krauth | |
109 * @author <a href="mailto:alex@purpletech.com">Alexander Day Chaffee</a> | |
110 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> | |
111 * @author Arun Mammen Thomas | |
112 * @author Gary Gregory | |
113 * @author Phil Steitz | |
114 * @author Al Chou | |
115 * @author Michael Davey | |
116 * @author Reuben Sivan | |
117 * @author Chris Hyzer | |
118 * @author Scott Johnson | |
119 * @version $Id: StringUtils.java 635447 2008-03-10 06:27:09Z bayard $ | |
120 * @see java.lang.String | |
121 * @since 1.0 | |
122 */ | |
123 public class StringUtils | |
124 { | |
125 // Performance testing notes (JDK 1.4, Jul03, scolebourne) | |
126 // Whitespace: | |
127 // Character.isWhitespace() is faster than WHITESPACE.indexOf() | |
128 // where WHITESPACE is a string of all whitespace characters | |
129 // | |
130 // Character access: | |
131 // String.charAt(n) versus toCharArray(), then array[n] | |
132 // String.charAt(n) is about 15% worse for a 10K string | |
133 // They are about equal for a length 50 string | |
134 // String.charAt(n) is about 4 times better for a length 3 string | |
135 // String.charAt(n) is best bet overall | |
136 // | |
137 // Append: | |
138 // String.concat about twice as fast as StringBuffer.append | |
139 // (not sure who tested this) | |
140 | |
141 /** | |
142 * The empty String <code>""</code>. | |
143 * | |
144 * @since 2.0 | |
145 */ | |
146 public static final String EMPTY = ""; | |
147 | |
148 /** | |
149 * Represents a failed index search. | |
150 * | |
151 * @since 2.1 | |
152 */ | |
153 public static final int INDEX_NOT_FOUND = -1; | |
154 | |
155 /** | |
156 * <p>The maximum size to which the padding constant(s) can expand.</p> | |
157 */ | |
158 private static final int PAD_LIMIT = 8192; | |
159 | |
160 /** | |
161 * <p><code>StringUtils</code> instances should NOT be constructed in | |
162 * standard programming. Instead, the class should be used as | |
163 * <code>StringUtils.trim(" foo ");</code>.</p> | |
164 * <p/> | |
165 * <p>This constructor is public to permit tools that require a JavaBean | |
166 * instance to operate.</p> | |
167 */ | |
168 public StringUtils() | |
169 { | |
170 super(); | |
171 } | |
172 | |
173 // Empty checks | |
174 //----------------------------------------------------------------------- | |
175 | |
176 /** | |
177 * <p>Checks if a String is empty ("") or null.</p> | |
178 * <p/> | |
179 * <pre> | |
180 * StringUtils.isEmpty(null) = true | |
181 * StringUtils.isEmpty("") = true | |
182 * StringUtils.isEmpty(" ") = false | |
183 * StringUtils.isEmpty("bob") = false | |
184 * StringUtils.isEmpty(" bob ") = false | |
185 * </pre> | |
186 * <p/> | |
187 * <p>NOTE: This method changed in Lang version 2.0. | |
188 * It no longer trims the String. | |
189 * That functionality is available in isBlank().</p> | |
190 * | |
191 * @param str the String to check, may be null | |
192 * @return <code>true</code> if the String is empty or null | |
193 */ | |
194 public static boolean isEmpty(String str) | |
195 { | |
196 return str == null || str.length() == 0; | |
197 } | |
198 | |
199 /** | |
200 * <p>Checks if a String is not empty ("") and not null.</p> | |
201 * <p/> | |
202 * <pre> | |
203 * StringUtils.isNotEmpty(null) = false | |
204 * StringUtils.isNotEmpty("") = false | |
205 * StringUtils.isNotEmpty(" ") = true | |
206 * StringUtils.isNotEmpty("bob") = true | |
207 * StringUtils.isNotEmpty(" bob ") = true | |
208 * </pre> | |
209 * | |
210 * @param str the String to check, may be null | |
211 * @return <code>true</code> if the String is not empty and not null | |
212 */ | |
213 public static boolean isNotEmpty(String str) | |
214 { | |
215 return !StringUtils.isEmpty(str); | |
216 } | |
217 | |
218 /** | |
219 * <p>Checks if a String is whitespace, empty ("") or null.</p> | |
220 * <p/> | |
221 * <pre> | |
222 * StringUtils.isBlank(null) = true | |
223 * StringUtils.isBlank("") = true | |
224 * StringUtils.isBlank(" ") = true | |
225 * StringUtils.isBlank("bob") = false | |
226 * StringUtils.isBlank(" bob ") = false | |
227 * </pre> | |
228 * | |
229 * @param str the String to check, may be null | |
230 * @return <code>true</code> if the String is null, empty or whitespace | |
231 * @since 2.0 | |
232 */ | |
233 public static boolean isBlank(String str) | |
234 { | |
235 int strLen; | |
236 if (str == null || (strLen = str.length()) == 0) | |
237 { | |
238 return true; | |
239 } | |
240 for (int i = 0; i < strLen; i++) | |
241 { | |
242 if ((Character.isWhitespace(str.charAt(i)) == false)) | |
243 { | |
244 return false; | |
245 } | |
246 } | |
247 return true; | |
248 } | |
249 | |
250 /** | |
251 * <p>Checks if a String is not empty (""), not null and not whitespace only.<
/p> | |
252 * <p/> | |
253 * <pre> | |
254 * StringUtils.isNotBlank(null) = false | |
255 * StringUtils.isNotBlank("") = false | |
256 * StringUtils.isNotBlank(" ") = false | |
257 * StringUtils.isNotBlank("bob") = true | |
258 * StringUtils.isNotBlank(" bob ") = true | |
259 * </pre> | |
260 * | |
261 * @param str the String to check, may be null | |
262 * @return <code>true</code> if the String is | |
263 * not empty and not null and not whitespace | |
264 * @since 2.0 | |
265 */ | |
266 public static boolean isNotBlank(String str) | |
267 { | |
268 return !StringUtils.isBlank(str); | |
269 } | |
270 | |
271 // Trim | |
272 //----------------------------------------------------------------------- | |
273 | |
274 /** | |
275 * <p>Removes control characters (char <= 32) from both | |
276 * ends of this String, handling <code>null</code> by returning | |
277 * an empty String ("").</p> | |
278 * <p/> | |
279 * <pre> | |
280 * StringUtils.clean(null) = "" | |
281 * StringUtils.clean("") = "" | |
282 * StringUtils.clean("abc") = "abc" | |
283 * StringUtils.clean(" abc ") = "abc" | |
284 * StringUtils.clean(" ") = "" | |
285 * </pre> | |
286 * | |
287 * @param str the String to clean, may be null | |
288 * @return the trimmed text, never <code>null</code> | |
289 * @see java.lang.String#trim() | |
290 * @deprecated Use the clearer named {@link #trimToEmpty(String)}. | |
291 * Method will be removed in Commons Lang 3.0. | |
292 */ | |
293 public static String clean(String str) | |
294 { | |
295 return str == null ? EMPTY : str.trim(); | |
296 } | |
297 | |
298 /** | |
299 * <p>Removes control characters (char <= 32) from both | |
300 * ends of this String, handling <code>null</code> by returning | |
301 * <code>null</code>.</p> | |
302 * <p/> | |
303 * <p>The String is trimmed using {@link String#trim()}. | |
304 * Trim removes start and end characters <= 32. | |
305 * To strip whitespace use {@link #strip(String)}.</p> | |
306 * <p/> | |
307 * <p>To trim your choice of characters, use the | |
308 * {@link #strip(String, String)} methods.</p> | |
309 * <p/> | |
310 * <pre> | |
311 * StringUtils.trim(null) = null | |
312 * StringUtils.trim("") = "" | |
313 * StringUtils.trim(" ") = "" | |
314 * StringUtils.trim("abc") = "abc" | |
315 * StringUtils.trim(" abc ") = "abc" | |
316 * </pre> | |
317 * | |
318 * @param str the String to be trimmed, may be null | |
319 * @return the trimmed string, <code>null</code> if null String input | |
320 */ | |
321 public static String trim(String str) | |
322 { | |
323 return str == null ? null : str.trim(); | |
324 } | |
325 | |
326 /** | |
327 * <p>Removes control characters (char <= 32) from both | |
328 * ends of this String returning <code>null</code> if the String is | |
329 * empty ("") after the trim or if it is <code>null</code>. | |
330 * <p/> | |
331 * <p>The String is trimmed using {@link String#trim()}. | |
332 * Trim removes start and end characters <= 32. | |
333 * To strip whitespace use {@link #stripToNull(String)}.</p> | |
334 * <p/> | |
335 * <pre> | |
336 * StringUtils.trimToNull(null) = null | |
337 * StringUtils.trimToNull("") = null | |
338 * StringUtils.trimToNull(" ") = null | |
339 * StringUtils.trimToNull("abc") = "abc" | |
340 * StringUtils.trimToNull(" abc ") = "abc" | |
341 * </pre> | |
342 * | |
343 * @param str the String to be trimmed, may be null | |
344 * @return the trimmed String, | |
345 * <code>null</code> if only chars <= 32, empty or null String input | |
346 * @since 2.0 | |
347 */ | |
348 public static String trimToNull(String str) | |
349 { | |
350 String ts = trim(str); | |
351 return isEmpty(ts) ? null : ts; | |
352 } | |
353 | |
354 /** | |
355 * <p>Removes control characters (char <= 32) from both | |
356 * ends of this String returning an empty String ("") if the String | |
357 * is empty ("") after the trim or if it is <code>null</code>. | |
358 * <p/> | |
359 * <p>The String is trimmed using {@link String#trim()}. | |
360 * Trim removes start and end characters <= 32. | |
361 * To strip whitespace use {@link #stripToEmpty(String)}.</p> | |
362 * <p/> | |
363 * <pre> | |
364 * StringUtils.trimToEmpty(null) = "" | |
365 * StringUtils.trimToEmpty("") = "" | |
366 * StringUtils.trimToEmpty(" ") = "" | |
367 * StringUtils.trimToEmpty("abc") = "abc" | |
368 * StringUtils.trimToEmpty(" abc ") = "abc" | |
369 * </pre> | |
370 * | |
371 * @param str the String to be trimmed, may be null | |
372 * @return the trimmed String, or an empty String if <code>null</code> input | |
373 * @since 2.0 | |
374 */ | |
375 public static String trimToEmpty(String str) | |
376 { | |
377 return str == null ? EMPTY : str.trim(); | |
378 } | |
379 | |
380 // Stripping | |
381 //----------------------------------------------------------------------- | |
382 | |
383 /** | |
384 * <p>Strips whitespace from the start and end of a String.</p> | |
385 * <p/> | |
386 * <p>This is similar to {@link #trim(String)} but removes whitespace. | |
387 * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> | |
388 * <p/> | |
389 * <p>A <code>null</code> input String returns <code>null</code>.</p> | |
390 * <p/> | |
391 * <pre> | |
392 * StringUtils.strip(null) = null | |
393 * StringUtils.strip("") = "" | |
394 * StringUtils.strip(" ") = "" | |
395 * StringUtils.strip("abc") = "abc" | |
396 * StringUtils.strip(" abc") = "abc" | |
397 * StringUtils.strip("abc ") = "abc" | |
398 * StringUtils.strip(" abc ") = "abc" | |
399 * StringUtils.strip(" ab c ") = "ab c" | |
400 * </pre> | |
401 * | |
402 * @param str the String to remove whitespace from, may be null | |
403 * @return the stripped String, <code>null</code> if null String input | |
404 */ | |
405 public static String strip(String str) | |
406 { | |
407 return strip(str, null); | |
408 } | |
409 | |
410 /** | |
411 * <p>Strips whitespace from the start and end of a String returning | |
412 * <code>null</code> if the String is empty ("") after the strip.</p> | |
413 * <p/> | |
414 * <p>This is similar to {@link #trimToNull(String)} but removes whitespace. | |
415 * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> | |
416 * <p/> | |
417 * <pre> | |
418 * StringUtils.stripToNull(null) = null | |
419 * StringUtils.stripToNull("") = null | |
420 * StringUtils.stripToNull(" ") = null | |
421 * StringUtils.stripToNull("abc") = "abc" | |
422 * StringUtils.stripToNull(" abc") = "abc" | |
423 * StringUtils.stripToNull("abc ") = "abc" | |
424 * StringUtils.stripToNull(" abc ") = "abc" | |
425 * StringUtils.stripToNull(" ab c ") = "ab c" | |
426 * </pre> | |
427 * | |
428 * @param str the String to be stripped, may be null | |
429 * @return the stripped String, | |
430 * <code>null</code> if whitespace, empty or null String input | |
431 * @since 2.0 | |
432 */ | |
433 public static String stripToNull(String str) | |
434 { | |
435 if (str == null) | |
436 { | |
437 return null; | |
438 } | |
439 str = strip(str, null); | |
440 return str.length() == 0 ? null : str; | |
441 } | |
442 | |
443 /** | |
444 * <p>Strips whitespace from the start and end of a String returning | |
445 * an empty String if <code>null</code> input.</p> | |
446 * <p/> | |
447 * <p>This is similar to {@link #trimToEmpty(String)} but removes whitespace. | |
448 * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> | |
449 * <p/> | |
450 * <pre> | |
451 * StringUtils.stripToEmpty(null) = "" | |
452 * StringUtils.stripToEmpty("") = "" | |
453 * StringUtils.stripToEmpty(" ") = "" | |
454 * StringUtils.stripToEmpty("abc") = "abc" | |
455 * StringUtils.stripToEmpty(" abc") = "abc" | |
456 * StringUtils.stripToEmpty("abc ") = "abc" | |
457 * StringUtils.stripToEmpty(" abc ") = "abc" | |
458 * StringUtils.stripToEmpty(" ab c ") = "ab c" | |
459 * </pre> | |
460 * | |
461 * @param str the String to be stripped, may be null | |
462 * @return the trimmed String, or an empty String if <code>null</code> input | |
463 * @since 2.0 | |
464 */ | |
465 public static String stripToEmpty(String str) | |
466 { | |
467 return str == null ? EMPTY : strip(str, null); | |
468 } | |
469 | |
470 /** | |
471 * <p>Strips any of a set of characters from the start and end of a String. | |
472 * This is similar to {@link String#trim()} but allows the characters | |
473 * to be stripped to be controlled.</p> | |
474 * <p/> | |
475 * <p>A <code>null</code> input String returns <code>null</code>. | |
476 * An empty string ("") input returns the empty string.</p> | |
477 * <p/> | |
478 * <p>If the stripChars String is <code>null</code>, whitespace is | |
479 * stripped as defined by {@link Character#isWhitespace(char)}. | |
480 * Alternatively use {@link #strip(String)}.</p> | |
481 * <p/> | |
482 * <pre> | |
483 * StringUtils.strip(null, *) = null | |
484 * StringUtils.strip("", *) = "" | |
485 * StringUtils.strip("abc", null) = "abc" | |
486 * StringUtils.strip(" abc", null) = "abc" | |
487 * StringUtils.strip("abc ", null) = "abc" | |
488 * StringUtils.strip(" abc ", null) = "abc" | |
489 * StringUtils.strip(" abcyx", "xyz") = " abc" | |
490 * </pre> | |
491 * | |
492 * @param str the String to remove characters from, may be null | |
493 * @param stripChars the characters to remove, null treated as whitespace | |
494 * @return the stripped String, <code>null</code> if null String input | |
495 */ | |
496 public static String strip(String str, String stripChars) | |
497 { | |
498 if (isEmpty(str)) | |
499 { | |
500 return str; | |
501 } | |
502 str = stripStart(str, stripChars); | |
503 return stripEnd(str, stripChars); | |
504 } | |
505 | |
506 /** | |
507 * <p>Strips any of a set of characters from the start of a String.</p> | |
508 * <p/> | |
509 * <p>A <code>null</code> input String returns <code>null</code>. | |
510 * An empty string ("") input returns the empty string.</p> | |
511 * <p/> | |
512 * <p>If the stripChars String is <code>null</code>, whitespace is | |
513 * stripped as defined by {@link Character#isWhitespace(char)}.</p> | |
514 * <p/> | |
515 * <pre> | |
516 * StringUtils.stripStart(null, *) = null | |
517 * StringUtils.stripStart("", *) = "" | |
518 * StringUtils.stripStart("abc", "") = "abc" | |
519 * StringUtils.stripStart("abc", null) = "abc" | |
520 * StringUtils.stripStart(" abc", null) = "abc" | |
521 * StringUtils.stripStart("abc ", null) = "abc " | |
522 * StringUtils.stripStart(" abc ", null) = "abc " | |
523 * StringUtils.stripStart("yxabc ", "xyz") = "abc " | |
524 * </pre> | |
525 * | |
526 * @param str the String to remove characters from, may be null | |
527 * @param stripChars the characters to remove, null treated as whitespace | |
528 * @return the stripped String, <code>null</code> if null String input | |
529 */ | |
530 public static String stripStart(String str, String stripChars) | |
531 { | |
532 int strLen; | |
533 if (str == null || (strLen = str.length()) == 0) | |
534 { | |
535 return str; | |
536 } | |
537 int start = 0; | |
538 if (stripChars == null) | |
539 { | |
540 while ((start != strLen) && Character.isWhitespace(str.charAt(start))) | |
541 { | |
542 start++; | |
543 } | |
544 } else if (stripChars.length() == 0) | |
545 { | |
546 return str; | |
547 } else | |
548 { | |
549 while ((start != strLen) && (stripChars.indexOf(str.charAt(start)) != -1)) | |
550 { | |
551 start++; | |
552 } | |
553 } | |
554 return str.substring(start); | |
555 } | |
556 | |
557 /** | |
558 * <p>Strips any of a set of characters from the end of a String.</p> | |
559 * <p/> | |
560 * <p>A <code>null</code> input String returns <code>null</code>. | |
561 * An empty string ("") input returns the empty string.</p> | |
562 * <p/> | |
563 * <p>If the stripChars String is <code>null</code>, whitespace is | |
564 * stripped as defined by {@link Character#isWhitespace(char)}.</p> | |
565 * <p/> | |
566 * <pre> | |
567 * StringUtils.stripEnd(null, *) = null | |
568 * StringUtils.stripEnd("", *) = "" | |
569 * StringUtils.stripEnd("abc", "") = "abc" | |
570 * StringUtils.stripEnd("abc", null) = "abc" | |
571 * StringUtils.stripEnd(" abc", null) = " abc" | |
572 * StringUtils.stripEnd("abc ", null) = "abc" | |
573 * StringUtils.stripEnd(" abc ", null) = " abc" | |
574 * StringUtils.stripEnd(" abcyx", "xyz") = " abc" | |
575 * </pre> | |
576 * | |
577 * @param str the String to remove characters from, may be null | |
578 * @param stripChars the characters to remove, null treated as whitespace | |
579 * @return the stripped String, <code>null</code> if null String input | |
580 */ | |
581 public static String stripEnd(String str, String stripChars) | |
582 { | |
583 int end; | |
584 if (str == null || (end = str.length()) == 0) | |
585 { | |
586 return str; | |
587 } | |
588 | |
589 if (stripChars == null) | |
590 { | |
591 while ((end != 0) && Character.isWhitespace(str.charAt(end - 1))) | |
592 { | |
593 end--; | |
594 } | |
595 } else if (stripChars.length() == 0) | |
596 { | |
597 return str; | |
598 } else | |
599 { | |
600 while ((end != 0) && (stripChars.indexOf(str.charAt(end - 1)) != -1)) | |
601 { | |
602 end--; | |
603 } | |
604 } | |
605 return str.substring(0, end); | |
606 } | |
607 | |
608 // StripAll | |
609 //----------------------------------------------------------------------- | |
610 | |
611 /** | |
612 * <p>Strips whitespace from the start and end of every String in an array. | |
613 * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> | |
614 * <p/> | |
615 * <p>A new array is returned each time, except for length zero. | |
616 * A <code>null</code> array will return <code>null</code>. | |
617 * An empty array will return itself. | |
618 * A <code>null</code> array entry will be ignored.</p> | |
619 * <p/> | |
620 * <pre> | |
621 * StringUtils.stripAll(null) = null | |
622 * StringUtils.stripAll([]) = [] | |
623 * StringUtils.stripAll(["abc", " abc"]) = ["abc", "abc"] | |
624 * StringUtils.stripAll(["abc ", null]) = ["abc", null] | |
625 * </pre> | |
626 * | |
627 * @param strs the array to remove whitespace from, may be null | |
628 * @return the stripped Strings, <code>null</code> if null array input | |
629 */ | |
630 public static String[] stripAll(String[] strs) | |
631 { | |
632 return stripAll(strs, null); | |
633 } | |
634 | |
635 /** | |
636 * <p>Strips any of a set of characters from the start and end of every | |
637 * String in an array.</p> | |
638 * Whitespace is defined by {@link Character#isWhitespace(char)}.</p> | |
639 * <p/> | |
640 * <p>A new array is returned each time, except for length zero. | |
641 * A <code>null</code> array will return <code>null</code>. | |
642 * An empty array will return itself. | |
643 * A <code>null</code> array entry will be ignored. | |
644 * A <code>null</code> stripChars will strip whitespace as defined by | |
645 * {@link Character#isWhitespace(char)}.</p> | |
646 * <p/> | |
647 * <pre> | |
648 * StringUtils.stripAll(null, *) = null | |
649 * StringUtils.stripAll([], *) = [] | |
650 * StringUtils.stripAll(["abc", " abc"], null) = ["abc", "abc"] | |
651 * StringUtils.stripAll(["abc ", null], null) = ["abc", null] | |
652 * StringUtils.stripAll(["abc ", null], "yz") = ["abc ", null] | |
653 * StringUtils.stripAll(["yabcz", null], "yz") = ["abc", null] | |
654 * </pre> | |
655 * | |
656 * @param strs the array to remove characters from, may be null | |
657 * @param stripChars the characters to remove, null treated as whitespace | |
658 * @return the stripped Strings, <code>null</code> if null array input | |
659 */ | |
660 public static String[] stripAll(String[] strs, String stripChars) | |
661 { | |
662 int strsLen; | |
663 if (strs == null || (strsLen = strs.length) == 0) | |
664 { | |
665 return strs; | |
666 } | |
667 String[] newArr = new String[strsLen]; | |
668 for (int i = 0; i < strsLen; i++) | |
669 { | |
670 newArr[i] = strip(strs[i], stripChars); | |
671 } | |
672 return newArr; | |
673 } | |
674 | |
675 // Equals | |
676 //----------------------------------------------------------------------- | |
677 | |
678 /** | |
679 * <p>Compares two Strings, returning <code>true</code> if they are equal.</p> | |
680 * <p/> | |
681 * <p><code>null</code>s are handled without exceptions. Two <code>null</code> | |
682 * references are considered to be equal. The comparison is case sensitive.</p
> | |
683 * <p/> | |
684 * <pre> | |
685 * StringUtils.equals(null, null) = true | |
686 * StringUtils.equals(null, "abc") = false | |
687 * StringUtils.equals("abc", null) = false | |
688 * StringUtils.equals("abc", "abc") = true | |
689 * StringUtils.equals("abc", "ABC") = false | |
690 * </pre> | |
691 * | |
692 * @param str1 the first String, may be null | |
693 * @param str2 the second String, may be null | |
694 * @return <code>true</code> if the Strings are equal, case sensitive, or | |
695 * both <code>null</code> | |
696 * @see java.lang.String#equals(Object) | |
697 */ | |
698 public static boolean equals(String str1, String str2) | |
699 { | |
700 return str1 == null ? str2 == null : str1.equals(str2); | |
701 } | |
702 | |
703 /** | |
704 * <p>Compares two Strings, returning <code>true</code> if they are equal igno
ring | |
705 * the case.</p> | |
706 * <p/> | |
707 * <p><code>null</code>s are handled without exceptions. Two <code>null</code> | |
708 * references are considered equal. Comparison is case insensitive.</p> | |
709 * <p/> | |
710 * <pre> | |
711 * StringUtils.equalsIgnoreCase(null, null) = true | |
712 * StringUtils.equalsIgnoreCase(null, "abc") = false | |
713 * StringUtils.equalsIgnoreCase("abc", null) = false | |
714 * StringUtils.equalsIgnoreCase("abc", "abc") = true | |
715 * StringUtils.equalsIgnoreCase("abc", "ABC") = true | |
716 * </pre> | |
717 * | |
718 * @param str1 the first String, may be null | |
719 * @param str2 the second String, may be null | |
720 * @return <code>true</code> if the Strings are equal, case insensitive, or | |
721 * both <code>null</code> | |
722 * @see java.lang.String#equalsIgnoreCase(String) | |
723 */ | |
724 public static boolean equalsIgnoreCase(String str1, String str2) | |
725 { | |
726 return str1 == null ? str2 == null : str1.equalsIgnoreCase(str2); | |
727 } | |
728 | |
729 // IndexOf | |
730 //----------------------------------------------------------------------- | |
731 | |
732 /** | |
733 * <p>Finds the first index within a String, handling <code>null</code>. | |
734 * This method uses {@link String#indexOf(int)}.</p> | |
735 * <p/> | |
736 * <p>A <code>null</code> or empty ("") String will return <code>-1</code>.</p
> | |
737 * <p/> | |
738 * <pre> | |
739 * StringUtils.indexOf(null, *) = -1 | |
740 * StringUtils.indexOf("", *) = -1 | |
741 * StringUtils.indexOf("aabaabaa", 'a') = 0 | |
742 * StringUtils.indexOf("aabaabaa", 'b') = 2 | |
743 * </pre> | |
744 * | |
745 * @param str the String to check, may be null | |
746 * @param searchChar the character to find | |
747 * @return the first index of the search character, | |
748 * -1 if no match or <code>null</code> string input | |
749 * @since 2.0 | |
750 */ | |
751 public static int indexOf(String str, char searchChar) | |
752 { | |
753 if (isEmpty(str)) | |
754 { | |
755 return -1; | |
756 } | |
757 return str.indexOf(searchChar); | |
758 } | |
759 | |
760 /** | |
761 * <p>Finds the first index within a String from a start position, | |
762 * handling <code>null</code>. | |
763 * This method uses {@link String#indexOf(int, int)}.</p> | |
764 * <p/> | |
765 * <p>A <code>null</code> or empty ("") String will return <code>-1</code>. | |
766 * A negative start position is treated as zero. | |
767 * A start position greater than the string length returns <code>-1</code>.</p
> | |
768 * <p/> | |
769 * <pre> | |
770 * StringUtils.indexOf(null, *, *) = -1 | |
771 * StringUtils.indexOf("", *, *) = -1 | |
772 * StringUtils.indexOf("aabaabaa", 'b', 0) = 2 | |
773 * StringUtils.indexOf("aabaabaa", 'b', 3) = 5 | |
774 * StringUtils.indexOf("aabaabaa", 'b', 9) = -1 | |
775 * StringUtils.indexOf("aabaabaa", 'b', -1) = 2 | |
776 * </pre> | |
777 * | |
778 * @param str the String to check, may be null | |
779 * @param searchChar the character to find | |
780 * @param startPos the start position, negative treated as zero | |
781 * @return the first index of the search character, | |
782 * -1 if no match or <code>null</code> string input | |
783 * @since 2.0 | |
784 */ | |
785 public static int indexOf(String str, char searchChar, int startPos) | |
786 { | |
787 if (isEmpty(str)) | |
788 { | |
789 return -1; | |
790 } | |
791 return str.indexOf(searchChar, startPos); | |
792 } | |
793 | |
794 /** | |
795 * <p>Finds the first index within a String, handling <code>null</code>. | |
796 * This method uses {@link String#indexOf(String)}.</p> | |
797 * <p/> | |
798 * <p>A <code>null</code> String will return <code>-1</code>.</p> | |
799 * <p/> | |
800 * <pre> | |
801 * StringUtils.indexOf(null, *) = -1 | |
802 * StringUtils.indexOf(*, null) = -1 | |
803 * StringUtils.indexOf("", "") = 0 | |
804 * StringUtils.indexOf("aabaabaa", "a") = 0 | |
805 * StringUtils.indexOf("aabaabaa", "b") = 2 | |
806 * StringUtils.indexOf("aabaabaa", "ab") = 1 | |
807 * StringUtils.indexOf("aabaabaa", "") = 0 | |
808 * </pre> | |
809 * | |
810 * @param str the String to check, may be null | |
811 * @param searchStr the String to find, may be null | |
812 * @return the first index of the search String, | |
813 * -1 if no match or <code>null</code> string input | |
814 * @since 2.0 | |
815 */ | |
816 public static int indexOf(String str, String searchStr) | |
817 { | |
818 if (str == null || searchStr == null) | |
819 { | |
820 return -1; | |
821 } | |
822 return str.indexOf(searchStr); | |
823 } | |
824 | |
825 /** | |
826 * <p>Finds the n-th index within a String, handling <code>null</code>. | |
827 * This method uses {@link String#indexOf(String)}.</p> | |
828 * <p/> | |
829 * <p>A <code>null</code> String will return <code>-1</code>.</p> | |
830 * <p/> | |
831 * <pre> | |
832 * StringUtils.ordinalIndexOf(null, *, *) = -1 | |
833 * StringUtils.ordinalIndexOf(*, null, *) = -1 | |
834 * StringUtils.ordinalIndexOf("", "", *) = 0 | |
835 * StringUtils.ordinalIndexOf("aabaabaa", "a", 1) = 0 | |
836 * StringUtils.ordinalIndexOf("aabaabaa", "a", 2) = 1 | |
837 * StringUtils.ordinalIndexOf("aabaabaa", "b", 1) = 2 | |
838 * StringUtils.ordinalIndexOf("aabaabaa", "b", 2) = 5 | |
839 * StringUtils.ordinalIndexOf("aabaabaa", "ab", 1) = 1 | |
840 * StringUtils.ordinalIndexOf("aabaabaa", "ab", 2) = 4 | |
841 * StringUtils.ordinalIndexOf("aabaabaa", "", 1) = 0 | |
842 * StringUtils.ordinalIndexOf("aabaabaa", "", 2) = 0 | |
843 * </pre> | |
844 * | |
845 * @param str the String to check, may be null | |
846 * @param searchStr the String to find, may be null | |
847 * @param ordinal the n-th <code>searchStr</code> to find | |
848 * @return the n-th index of the search String, | |
849 * <code>-1</code> (<code>INDEX_NOT_FOUND</code>) if no match or <code>null</c
ode> string input | |
850 * @since 2.1 | |
851 */ | |
852 public static int ordinalIndexOf(String str, String searchStr, int ordinal) | |
853 { | |
854 if (str == null || searchStr == null || ordinal <= 0) | |
855 { | |
856 return INDEX_NOT_FOUND; | |
857 } | |
858 if (searchStr.length() == 0) | |
859 { | |
860 return 0; | |
861 } | |
862 int found = 0; | |
863 int index = INDEX_NOT_FOUND; | |
864 do | |
865 { | |
866 index = str.indexOf(searchStr, index + 1); | |
867 if (index < 0) | |
868 { | |
869 return index; | |
870 } | |
871 found++; | |
872 } while (found < ordinal); | |
873 return index; | |
874 } | |
875 | |
876 /** | |
877 * <p>Finds the first index within a String, handling <code>null</code>. | |
878 * This method uses {@link String#indexOf(String, int)}.</p> | |
879 * <p/> | |
880 * <p>A <code>null</code> String will return <code>-1</code>. | |
881 * A negative start position is treated as zero. | |
882 * An empty ("") search String always matches. | |
883 * A start position greater than the string length only matches | |
884 * an empty search String.</p> | |
885 * <p/> | |
886 * <pre> | |
887 * StringUtils.indexOf(null, *, *) = -1 | |
888 * StringUtils.indexOf(*, null, *) = -1 | |
889 * StringUtils.indexOf("", "", 0) = 0 | |
890 * StringUtils.indexOf("aabaabaa", "a", 0) = 0 | |
891 * StringUtils.indexOf("aabaabaa", "b", 0) = 2 | |
892 * StringUtils.indexOf("aabaabaa", "ab", 0) = 1 | |
893 * StringUtils.indexOf("aabaabaa", "b", 3) = 5 | |
894 * StringUtils.indexOf("aabaabaa", "b", 9) = -1 | |
895 * StringUtils.indexOf("aabaabaa", "b", -1) = 2 | |
896 * StringUtils.indexOf("aabaabaa", "", 2) = 2 | |
897 * StringUtils.indexOf("abc", "", 9) = 3 | |
898 * </pre> | |
899 * | |
900 * @param str the String to check, may be null | |
901 * @param searchStr the String to find, may be null | |
902 * @param startPos the start position, negative treated as zero | |
903 * @return the first index of the search String, | |
904 * -1 if no match or <code>null</code> string input | |
905 * @since 2.0 | |
906 */ | |
907 public static int indexOf(String str, String searchStr, int startPos) | |
908 { | |
909 if (str == null || searchStr == null) | |
910 { | |
911 return -1; | |
912 } | |
913 // JDK1.2/JDK1.3 have a bug, when startPos > str.length for "", hence | |
914 if (searchStr.length() == 0 && startPos >= str.length()) | |
915 { | |
916 return str.length(); | |
917 } | |
918 return str.indexOf(searchStr, startPos); | |
919 } | |
920 | |
921 // LastIndexOf | |
922 //----------------------------------------------------------------------- | |
923 | |
924 /** | |
925 * <p>Finds the last index within a String, handling <code>null</code>. | |
926 * This method uses {@link String#lastIndexOf(int)}.</p> | |
927 * <p/> | |
928 * <p>A <code>null</code> or empty ("") String will return <code>-1</code>.</p
> | |
929 * <p/> | |
930 * <pre> | |
931 * StringUtils.lastIndexOf(null, *) = -1 | |
932 * StringUtils.lastIndexOf("", *) = -1 | |
933 * StringUtils.lastIndexOf("aabaabaa", 'a') = 7 | |
934 * StringUtils.lastIndexOf("aabaabaa", 'b') = 5 | |
935 * </pre> | |
936 * | |
937 * @param str the String to check, may be null | |
938 * @param searchChar the character to find | |
939 * @return the last index of the search character, | |
940 * -1 if no match or <code>null</code> string input | |
941 * @since 2.0 | |
942 */ | |
943 public static int lastIndexOf(String str, char searchChar) | |
944 { | |
945 if (isEmpty(str)) | |
946 { | |
947 return -1; | |
948 } | |
949 return str.lastIndexOf(searchChar); | |
950 } | |
951 | |
952 /** | |
953 * <p>Finds the last index within a String from a start position, | |
954 * handling <code>null</code>. | |
955 * This method uses {@link String#lastIndexOf(int, int)}.</p> | |
956 * <p/> | |
957 * <p>A <code>null</code> or empty ("") String will return <code>-1</code>. | |
958 * A negative start position returns <code>-1</code>. | |
959 * A start position greater than the string length searches the whole string.<
/p> | |
960 * <p/> | |
961 * <pre> | |
962 * StringUtils.lastIndexOf(null, *, *) = -1 | |
963 * StringUtils.lastIndexOf("", *, *) = -1 | |
964 * StringUtils.lastIndexOf("aabaabaa", 'b', 8) = 5 | |
965 * StringUtils.lastIndexOf("aabaabaa", 'b', 4) = 2 | |
966 * StringUtils.lastIndexOf("aabaabaa", 'b', 0) = -1 | |
967 * StringUtils.lastIndexOf("aabaabaa", 'b', 9) = 5 | |
968 * StringUtils.lastIndexOf("aabaabaa", 'b', -1) = -1 | |
969 * StringUtils.lastIndexOf("aabaabaa", 'a', 0) = 0 | |
970 * </pre> | |
971 * | |
972 * @param str the String to check, may be null | |
973 * @param searchChar the character to find | |
974 * @param startPos the start position | |
975 * @return the last index of the search character, | |
976 * -1 if no match or <code>null</code> string input | |
977 * @since 2.0 | |
978 */ | |
979 public static int lastIndexOf(String str, char searchChar, int startPos) | |
980 { | |
981 if (isEmpty(str)) | |
982 { | |
983 return -1; | |
984 } | |
985 return str.lastIndexOf(searchChar, startPos); | |
986 } | |
987 | |
988 /** | |
989 * <p>Finds the last index within a String, handling <code>null</code>. | |
990 * This method uses {@link String#lastIndexOf(String)}.</p> | |
991 * <p/> | |
992 * <p>A <code>null</code> String will return <code>-1</code>.</p> | |
993 * <p/> | |
994 * <pre> | |
995 * StringUtils.lastIndexOf(null, *) = -1 | |
996 * StringUtils.lastIndexOf(*, null) = -1 | |
997 * StringUtils.lastIndexOf("", "") = 0 | |
998 * StringUtils.lastIndexOf("aabaabaa", "a") = 0 | |
999 * StringUtils.lastIndexOf("aabaabaa", "b") = 2 | |
1000 * StringUtils.lastIndexOf("aabaabaa", "ab") = 1 | |
1001 * StringUtils.lastIndexOf("aabaabaa", "") = 8 | |
1002 * </pre> | |
1003 * | |
1004 * @param str the String to check, may be null | |
1005 * @param searchStr the String to find, may be null | |
1006 * @return the last index of the search String, | |
1007 * -1 if no match or <code>null</code> string input | |
1008 * @since 2.0 | |
1009 */ | |
1010 public static int lastIndexOf(String str, String searchStr) | |
1011 { | |
1012 if (str == null || searchStr == null) | |
1013 { | |
1014 return -1; | |
1015 } | |
1016 return str.lastIndexOf(searchStr); | |
1017 } | |
1018 | |
1019 /** | |
1020 * <p>Finds the first index within a String, handling <code>null</code>. | |
1021 * This method uses {@link String#lastIndexOf(String, int)}.</p> | |
1022 * <p/> | |
1023 * <p>A <code>null</code> String will return <code>-1</code>. | |
1024 * A negative start position returns <code>-1</code>. | |
1025 * An empty ("") search String always matches unless the start position is neg
ative. | |
1026 * A start position greater than the string length searches the whole string.<
/p> | |
1027 * <p/> | |
1028 * <pre> | |
1029 * StringUtils.lastIndexOf(null, *, *) = -1 | |
1030 * StringUtils.lastIndexOf(*, null, *) = -1 | |
1031 * StringUtils.lastIndexOf("aabaabaa", "a", 8) = 7 | |
1032 * StringUtils.lastIndexOf("aabaabaa", "b", 8) = 5 | |
1033 * StringUtils.lastIndexOf("aabaabaa", "ab", 8) = 4 | |
1034 * StringUtils.lastIndexOf("aabaabaa", "b", 9) = 5 | |
1035 * StringUtils.lastIndexOf("aabaabaa", "b", -1) = -1 | |
1036 * StringUtils.lastIndexOf("aabaabaa", "a", 0) = 0 | |
1037 * StringUtils.lastIndexOf("aabaabaa", "b", 0) = -1 | |
1038 * </pre> | |
1039 * | |
1040 * @param str the String to check, may be null | |
1041 * @param searchStr the String to find, may be null | |
1042 * @param startPos the start position, negative treated as zero | |
1043 * @return the first index of the search String, | |
1044 * -1 if no match or <code>null</code> string input | |
1045 * @since 2.0 | |
1046 */ | |
1047 public static int lastIndexOf(String str, String searchStr, int startPos) | |
1048 { | |
1049 if (str == null || searchStr == null) | |
1050 { | |
1051 return -1; | |
1052 } | |
1053 return str.lastIndexOf(searchStr, startPos); | |
1054 } | |
1055 | |
1056 // Contains | |
1057 //----------------------------------------------------------------------- | |
1058 | |
1059 /** | |
1060 * <p>Checks if String contains a search character, handling <code>null</code>
. | |
1061 * This method uses {@link String#indexOf(int)}.</p> | |
1062 * <p/> | |
1063 * <p>A <code>null</code> or empty ("") String will return <code>false</code>.
</p> | |
1064 * <p/> | |
1065 * <pre> | |
1066 * StringUtils.contains(null, *) = false | |
1067 * StringUtils.contains("", *) = false | |
1068 * StringUtils.contains("abc", 'a') = true | |
1069 * StringUtils.contains("abc", 'z') = false | |
1070 * </pre> | |
1071 * | |
1072 * @param str the String to check, may be null | |
1073 * @param searchChar the character to find | |
1074 * @return true if the String contains the search character, | |
1075 * false if not or <code>null</code> string input | |
1076 * @since 2.0 | |
1077 */ | |
1078 public static boolean contains(String str, char searchChar) | |
1079 { | |
1080 if (isEmpty(str)) | |
1081 { | |
1082 return false; | |
1083 } | |
1084 return str.indexOf(searchChar) >= 0; | |
1085 } | |
1086 | |
1087 /** | |
1088 * <p>Checks if String contains a search String, handling <code>null</code>. | |
1089 * This method uses {@link String#indexOf(String)}.</p> | |
1090 * <p/> | |
1091 * <p>A <code>null</code> String will return <code>false</code>.</p> | |
1092 * <p/> | |
1093 * <pre> | |
1094 * StringUtils.contains(null, *) = false | |
1095 * StringUtils.contains(*, null) = false | |
1096 * StringUtils.contains("", "") = true | |
1097 * StringUtils.contains("abc", "") = true | |
1098 * StringUtils.contains("abc", "a") = true | |
1099 * StringUtils.contains("abc", "z") = false | |
1100 * </pre> | |
1101 * | |
1102 * @param str the String to check, may be null | |
1103 * @param searchStr the String to find, may be null | |
1104 * @return true if the String contains the search String, | |
1105 * false if not or <code>null</code> string input | |
1106 * @since 2.0 | |
1107 */ | |
1108 public static boolean contains(String str, String searchStr) | |
1109 { | |
1110 if (str == null || searchStr == null) | |
1111 { | |
1112 return false; | |
1113 } | |
1114 return str.indexOf(searchStr) >= 0; | |
1115 } | |
1116 | |
1117 /** | |
1118 * <p>Checks if String contains a search String irrespective of case, | |
1119 * handling <code>null</code>. This method uses | |
1120 * {@link #contains(String, String)}.</p> | |
1121 * <p/> | |
1122 * <p>A <code>null</code> String will return <code>false</code>.</p> | |
1123 * <p/> | |
1124 * <pre> | |
1125 * StringUtils.contains(null, *) = false | |
1126 * StringUtils.contains(*, null) = false | |
1127 * StringUtils.contains("", "") = true | |
1128 * StringUtils.contains("abc", "") = true | |
1129 * StringUtils.contains("abc", "a") = true | |
1130 * StringUtils.contains("abc", "z") = false | |
1131 * StringUtils.contains("abc", "A") = true | |
1132 * StringUtils.contains("abc", "Z") = false | |
1133 * </pre> | |
1134 * | |
1135 * @param str the String to check, may be null | |
1136 * @param searchStr the String to find, may be null | |
1137 * @return true if the String contains the search String irrespective of | |
1138 * case or false if not or <code>null</code> string input | |
1139 */ | |
1140 public static boolean containsIgnoreCase(String str, String searchStr) | |
1141 { | |
1142 if (str == null || searchStr == null) | |
1143 { | |
1144 return false; | |
1145 } | |
1146 return contains(str.toUpperCase(), searchStr.toUpperCase()); | |
1147 } | |
1148 | |
1149 // ContainsAny | |
1150 //----------------------------------------------------------------------- | |
1151 | |
1152 /** | |
1153 * <p>Checks if the String contains any character in the given | |
1154 * set of characters.</p> | |
1155 * <p/> | |
1156 * <p>A <code>null</code> String will return <code>false</code>. | |
1157 * A <code>null</code> or zero length search array will return <code>false</co
de>.</p> | |
1158 * <p/> | |
1159 * <pre> | |
1160 * StringUtils.containsAny(null, *) = false | |
1161 * StringUtils.containsAny("", *) = false | |
1162 * StringUtils.containsAny(*, null) = false | |
1163 * StringUtils.containsAny(*, []) = false | |
1164 * StringUtils.containsAny("zzabyycdxx",['z','a']) = true | |
1165 * StringUtils.containsAny("zzabyycdxx",['b','y']) = true | |
1166 * StringUtils.containsAny("aba", ['z']) = false | |
1167 * </pre> | |
1168 * | |
1169 * @param str the String to check, may be null | |
1170 * @param searchChars the chars to search for, may be null | |
1171 * @return the <code>true</code> if any of the chars are found, | |
1172 * <code>false</code> if no match or null input | |
1173 * @since 2.4 | |
1174 */ | |
1175 public static boolean containsAny(String str, char[] searchChars) | |
1176 { | |
1177 if (str == null || str.length() == 0 || searchChars == null || searchChars.l
ength == 0) | |
1178 { | |
1179 return false; | |
1180 } | |
1181 for (int i = 0; i < str.length(); i++) | |
1182 { | |
1183 char ch = str.charAt(i); | |
1184 for (int j = 0; j < searchChars.length; j++) | |
1185 { | |
1186 if (searchChars[j] == ch) | |
1187 { | |
1188 return true; | |
1189 } | |
1190 } | |
1191 } | |
1192 return false; | |
1193 } | |
1194 | |
1195 /** | |
1196 * <p> | |
1197 * Checks if the String contains any character in the given set of characters. | |
1198 * </p> | |
1199 * <p/> | |
1200 * <p> | |
1201 * A <code>null</code> String will return <code>false</code>. A <code>null</co
de> search string will return | |
1202 * <code>false</code>. | |
1203 * </p> | |
1204 * <p/> | |
1205 * <pre> | |
1206 * StringUtils.containsAny(null, *) = false | |
1207 * StringUtils.containsAny("", *) = false | |
1208 * StringUtils.containsAny(*, null) = false | |
1209 * StringUtils.containsAny(*, "") = false | |
1210 * StringUtils.containsAny("zzabyycdxx", "za") = true | |
1211 * StringUtils.containsAny("zzabyycdxx", "by") = true | |
1212 * StringUtils.containsAny("aba","z") = false | |
1213 * </pre> | |
1214 * | |
1215 * @param str the String to check, may be null | |
1216 * @param searchChars the chars to search for, may be null | |
1217 * @return the <code>true</code> if any of the chars are found, <code>false</c
ode> if no match or null input | |
1218 * @since 2.4 | |
1219 */ | |
1220 public static boolean containsAny(String str, String searchChars) | |
1221 { | |
1222 if (searchChars == null) | |
1223 { | |
1224 return false; | |
1225 } | |
1226 return containsAny(str, searchChars.toCharArray()); | |
1227 } | |
1228 | |
1229 /** | |
1230 * <p>Search a String to find the first index of any | |
1231 * character not in the given set of characters.</p> | |
1232 * <p/> | |
1233 * <p>A <code>null</code> String will return <code>-1</code>. | |
1234 * A <code>null</code> search string will return <code>-1</code>.</p> | |
1235 * <p/> | |
1236 * <pre> | |
1237 * StringUtils.indexOfAnyBut(null, *) = -1 | |
1238 * StringUtils.indexOfAnyBut("", *) = -1 | |
1239 * StringUtils.indexOfAnyBut(*, null) = -1 | |
1240 * StringUtils.indexOfAnyBut(*, "") = -1 | |
1241 * StringUtils.indexOfAnyBut("zzabyycdxx", "za") = 3 | |
1242 * StringUtils.indexOfAnyBut("zzabyycdxx", "") = 0 | |
1243 * StringUtils.indexOfAnyBut("aba","ab") = -1 | |
1244 * </pre> | |
1245 * | |
1246 * @param str the String to check, may be null | |
1247 * @param searchChars the chars to search for, may be null | |
1248 * @return the index of any of the chars, -1 if no match or null input | |
1249 * @since 2.0 | |
1250 */ | |
1251 public static int indexOfAnyBut(String str, String searchChars) | |
1252 { | |
1253 if (isEmpty(str) || isEmpty(searchChars)) | |
1254 { | |
1255 return -1; | |
1256 } | |
1257 for (int i = 0; i < str.length(); i++) | |
1258 { | |
1259 if (searchChars.indexOf(str.charAt(i)) < 0) | |
1260 { | |
1261 return i; | |
1262 } | |
1263 } | |
1264 return -1; | |
1265 } | |
1266 | |
1267 // ContainsNone | |
1268 //----------------------------------------------------------------------- | |
1269 | |
1270 /** | |
1271 * <p>Checks that the String does not contain certain characters.</p> | |
1272 * <p/> | |
1273 * <p>A <code>null</code> String will return <code>true</code>. | |
1274 * A <code>null</code> invalid character array will return <code>true</code>. | |
1275 * An empty String ("") always returns true.</p> | |
1276 * <p/> | |
1277 * <pre> | |
1278 * StringUtils.containsNone(null, *) = true | |
1279 * StringUtils.containsNone(*, null) = true | |
1280 * StringUtils.containsNone("", *) = true | |
1281 * StringUtils.containsNone("ab", '') = true | |
1282 * StringUtils.containsNone("abab", 'xyz') = true | |
1283 * StringUtils.containsNone("ab1", 'xyz') = true | |
1284 * StringUtils.containsNone("abz", 'xyz') = false | |
1285 * </pre> | |
1286 * | |
1287 * @param str the String to check, may be null | |
1288 * @param invalidChars an array of invalid chars, may be null | |
1289 * @return true if it contains none of the invalid chars, or is null | |
1290 * @since 2.0 | |
1291 */ | |
1292 public static boolean containsNone(String str, char[] invalidChars) | |
1293 { | |
1294 if (str == null || invalidChars == null) | |
1295 { | |
1296 return true; | |
1297 } | |
1298 int strSize = str.length(); | |
1299 int validSize = invalidChars.length; | |
1300 for (int i = 0; i < strSize; i++) | |
1301 { | |
1302 char ch = str.charAt(i); | |
1303 for (int j = 0; j < validSize; j++) | |
1304 { | |
1305 if (invalidChars[j] == ch) | |
1306 { | |
1307 return false; | |
1308 } | |
1309 } | |
1310 } | |
1311 return true; | |
1312 } | |
1313 | |
1314 /** | |
1315 * <p>Checks that the String does not contain certain characters.</p> | |
1316 * <p/> | |
1317 * <p>A <code>null</code> String will return <code>true</code>. | |
1318 * A <code>null</code> invalid character array will return <code>true</code>. | |
1319 * An empty String ("") always returns true.</p> | |
1320 * <p/> | |
1321 * <pre> | |
1322 * StringUtils.containsNone(null, *) = true | |
1323 * StringUtils.containsNone(*, null) = true | |
1324 * StringUtils.containsNone("", *) = true | |
1325 * StringUtils.containsNone("ab", "") = true | |
1326 * StringUtils.containsNone("abab", "xyz") = true | |
1327 * StringUtils.containsNone("ab1", "xyz") = true | |
1328 * StringUtils.containsNone("abz", "xyz") = false | |
1329 * </pre> | |
1330 * | |
1331 * @param str the String to check, may be null | |
1332 * @param invalidChars a String of invalid chars, may be null | |
1333 * @return true if it contains none of the invalid chars, or is null | |
1334 * @since 2.0 | |
1335 */ | |
1336 public static boolean containsNone(String str, String invalidChars) | |
1337 { | |
1338 if (str == null || invalidChars == null) | |
1339 { | |
1340 return true; | |
1341 } | |
1342 return containsNone(str, invalidChars.toCharArray()); | |
1343 } | |
1344 | |
1345 // IndexOfAny strings | |
1346 //----------------------------------------------------------------------- | |
1347 | |
1348 /** | |
1349 * <p>Find the first index of any of a set of potential substrings.</p> | |
1350 * <p/> | |
1351 * <p>A <code>null</code> String will return <code>-1</code>. | |
1352 * A <code>null</code> or zero length search array will return <code>-1</code>
. | |
1353 * A <code>null</code> search array entry will be ignored, but a search | |
1354 * array containing "" will return <code>0</code> if <code>str</code> is not | |
1355 * null. This method uses {@link String#indexOf(String)}.</p> | |
1356 * <p/> | |
1357 * <pre> | |
1358 * StringUtils.indexOfAny(null, *) = -1 | |
1359 * StringUtils.indexOfAny(*, null) = -1 | |
1360 * StringUtils.indexOfAny(*, []) = -1 | |
1361 * StringUtils.indexOfAny("zzabyycdxx", ["ab","cd"]) = 2 | |
1362 * StringUtils.indexOfAny("zzabyycdxx", ["cd","ab"]) = 2 | |
1363 * StringUtils.indexOfAny("zzabyycdxx", ["mn","op"]) = -1 | |
1364 * StringUtils.indexOfAny("zzabyycdxx", ["zab","aby"]) = 1 | |
1365 * StringUtils.indexOfAny("zzabyycdxx", [""]) = 0 | |
1366 * StringUtils.indexOfAny("", [""]) = 0 | |
1367 * StringUtils.indexOfAny("", ["a"]) = -1 | |
1368 * </pre> | |
1369 * | |
1370 * @param str the String to check, may be null | |
1371 * @param searchStrs the Strings to search for, may be null | |
1372 * @return the first index of any of the searchStrs in str, -1 if no match | |
1373 */ | |
1374 public static int indexOfAny(String str, String[] searchStrs) | |
1375 { | |
1376 if ((str == null) || (searchStrs == null)) | |
1377 { | |
1378 return -1; | |
1379 } | |
1380 int sz = searchStrs.length; | |
1381 | |
1382 // String's can't have a MAX_VALUEth index. | |
1383 int ret = Integer.MAX_VALUE; | |
1384 | |
1385 int tmp = 0; | |
1386 for (int i = 0; i < sz; i++) | |
1387 { | |
1388 String search = searchStrs[i]; | |
1389 if (search == null) | |
1390 { | |
1391 continue; | |
1392 } | |
1393 tmp = str.indexOf(search); | |
1394 if (tmp == -1) | |
1395 { | |
1396 continue; | |
1397 } | |
1398 | |
1399 if (tmp < ret) | |
1400 { | |
1401 ret = tmp; | |
1402 } | |
1403 } | |
1404 | |
1405 return (ret == Integer.MAX_VALUE) ? -1 : ret; | |
1406 } | |
1407 | |
1408 /** | |
1409 * <p>Find the latest index of any of a set of potential substrings.</p> | |
1410 * <p/> | |
1411 * <p>A <code>null</code> String will return <code>-1</code>. | |
1412 * A <code>null</code> search array will return <code>-1</code>. | |
1413 * A <code>null</code> or zero length search array entry will be ignored, | |
1414 * but a search array containing "" will return the length of <code>str</code> | |
1415 * if <code>str</code> is not null. This method uses {@link String#indexOf(Str
ing)}</p> | |
1416 * <p/> | |
1417 * <pre> | |
1418 * StringUtils.lastIndexOfAny(null, *) = -1 | |
1419 * StringUtils.lastIndexOfAny(*, null) = -1 | |
1420 * StringUtils.lastIndexOfAny(*, []) = -1 | |
1421 * StringUtils.lastIndexOfAny(*, [null]) = -1 | |
1422 * StringUtils.lastIndexOfAny("zzabyycdxx", ["ab","cd"]) = 6 | |
1423 * StringUtils.lastIndexOfAny("zzabyycdxx", ["cd","ab"]) = 6 | |
1424 * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn","op"]) = -1 | |
1425 * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn","op"]) = -1 | |
1426 * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn",""]) = 10 | |
1427 * </pre> | |
1428 * | |
1429 * @param str the String to check, may be null | |
1430 * @param searchStrs the Strings to search for, may be null | |
1431 * @return the last index of any of the Strings, -1 if no match | |
1432 */ | |
1433 public static int lastIndexOfAny(String str, String[] searchStrs) | |
1434 { | |
1435 if ((str == null) || (searchStrs == null)) | |
1436 { | |
1437 return -1; | |
1438 } | |
1439 int sz = searchStrs.length; | |
1440 int ret = -1; | |
1441 int tmp = 0; | |
1442 for (int i = 0; i < sz; i++) | |
1443 { | |
1444 String search = searchStrs[i]; | |
1445 if (search == null) | |
1446 { | |
1447 continue; | |
1448 } | |
1449 tmp = str.lastIndexOf(search); | |
1450 if (tmp > ret) | |
1451 { | |
1452 ret = tmp; | |
1453 } | |
1454 } | |
1455 return ret; | |
1456 } | |
1457 | |
1458 // Substring | |
1459 //----------------------------------------------------------------------- | |
1460 | |
1461 /** | |
1462 * <p>Gets a substring from the specified String avoiding exceptions.</p> | |
1463 * <p/> | |
1464 * <p>A negative start position can be used to start <code>n</code> | |
1465 * characters from the end of the String.</p> | |
1466 * <p/> | |
1467 * <p>A <code>null</code> String will return <code>null</code>. | |
1468 * An empty ("") String will return "".</p> | |
1469 * <p/> | |
1470 * <pre> | |
1471 * StringUtils.substring(null, *) = null | |
1472 * StringUtils.substring("", *) = "" | |
1473 * StringUtils.substring("abc", 0) = "abc" | |
1474 * StringUtils.substring("abc", 2) = "c" | |
1475 * StringUtils.substring("abc", 4) = "" | |
1476 * StringUtils.substring("abc", -2) = "bc" | |
1477 * StringUtils.substring("abc", -4) = "abc" | |
1478 * </pre> | |
1479 * | |
1480 * @param str the String to get the substring from, may be null | |
1481 * @param start the position to start from, negative means | |
1482 * count back from the end of the String by this many characters | |
1483 * @return substring from start position, <code>null</code> if null String inp
ut | |
1484 */ | |
1485 public static String substring(String str, int start) | |
1486 { | |
1487 if (str == null) | |
1488 { | |
1489 return null; | |
1490 } | |
1491 | |
1492 // handle negatives, which means last n characters | |
1493 if (start < 0) | |
1494 { | |
1495 start = str.length() + start; // remember start is negative | |
1496 } | |
1497 | |
1498 if (start < 0) | |
1499 { | |
1500 start = 0; | |
1501 } | |
1502 if (start > str.length()) | |
1503 { | |
1504 return EMPTY; | |
1505 } | |
1506 | |
1507 return str.substring(start); | |
1508 } | |
1509 | |
1510 /** | |
1511 * <p>Gets a substring from the specified String avoiding exceptions.</p> | |
1512 * <p/> | |
1513 * <p>A negative start position can be used to start/end <code>n</code> | |
1514 * characters from the end of the String.</p> | |
1515 * <p/> | |
1516 * <p>The returned substring starts with the character in the <code>start</cod
e> | |
1517 * position and ends before the <code>end</code> position. All position counti
ng is | |
1518 * zero-based -- i.e., to start at the beginning of the string use | |
1519 * <code>start = 0</code>. Negative start and end positions can be used to | |
1520 * specify offsets relative to the end of the String.</p> | |
1521 * <p/> | |
1522 * <p>If <code>start</code> is not strictly to the left of <code>end</code>, "
" | |
1523 * is returned.</p> | |
1524 * <p/> | |
1525 * <pre> | |
1526 * StringUtils.substring(null, *, *) = null | |
1527 * StringUtils.substring("", * , *) = ""; | |
1528 * StringUtils.substring("abc", 0, 2) = "ab" | |
1529 * StringUtils.substring("abc", 2, 0) = "" | |
1530 * StringUtils.substring("abc", 2, 4) = "c" | |
1531 * StringUtils.substring("abc", 4, 6) = "" | |
1532 * StringUtils.substring("abc", 2, 2) = "" | |
1533 * StringUtils.substring("abc", -2, -1) = "b" | |
1534 * StringUtils.substring("abc", -4, 2) = "ab" | |
1535 * </pre> | |
1536 * | |
1537 * @param str the String to get the substring from, may be null | |
1538 * @param start the position to start from, negative means | |
1539 * count back from the end of the String by this many characters | |
1540 * @param end the position to end at (exclusive), negative means | |
1541 * count back from the end of the String by this many characters | |
1542 * @return substring from start position to end positon, | |
1543 * <code>null</code> if null String input | |
1544 */ | |
1545 public static String substring(String str, int start, int end) | |
1546 { | |
1547 if (str == null) | |
1548 { | |
1549 return null; | |
1550 } | |
1551 | |
1552 // handle negatives | |
1553 if (end < 0) | |
1554 { | |
1555 end = str.length() + end; // remember end is negative | |
1556 } | |
1557 if (start < 0) | |
1558 { | |
1559 start = str.length() + start; // remember start is negative | |
1560 } | |
1561 | |
1562 // check length next | |
1563 if (end > str.length()) | |
1564 { | |
1565 end = str.length(); | |
1566 } | |
1567 | |
1568 // if start is greater than end, return "" | |
1569 if (start > end) | |
1570 { | |
1571 return EMPTY; | |
1572 } | |
1573 | |
1574 if (start < 0) | |
1575 { | |
1576 start = 0; | |
1577 } | |
1578 if (end < 0) | |
1579 { | |
1580 end = 0; | |
1581 } | |
1582 | |
1583 return str.substring(start, end); | |
1584 } | |
1585 | |
1586 // Left/Right/Mid | |
1587 //----------------------------------------------------------------------- | |
1588 | |
1589 /** | |
1590 * <p>Gets the leftmost <code>len</code> characters of a String.</p> | |
1591 * <p/> | |
1592 * <p>If <code>len</code> characters are not available, or the | |
1593 * String is <code>null</code>, the String will be returned without | |
1594 * an exception. An exception is thrown if len is negative.</p> | |
1595 * <p/> | |
1596 * <pre> | |
1597 * StringUtils.left(null, *) = null | |
1598 * StringUtils.left(*, -ve) = "" | |
1599 * StringUtils.left("", *) = "" | |
1600 * StringUtils.left("abc", 0) = "" | |
1601 * StringUtils.left("abc", 2) = "ab" | |
1602 * StringUtils.left("abc", 4) = "abc" | |
1603 * </pre> | |
1604 * | |
1605 * @param str the String to get the leftmost characters from, may be null | |
1606 * @param len the length of the required String, must be zero or positive | |
1607 * @return the leftmost characters, <code>null</code> if null String input | |
1608 */ | |
1609 public static String left(String str, int len) | |
1610 { | |
1611 if (str == null) | |
1612 { | |
1613 return null; | |
1614 } | |
1615 if (len < 0) | |
1616 { | |
1617 return EMPTY; | |
1618 } | |
1619 if (str.length() <= len) | |
1620 { | |
1621 return str; | |
1622 } | |
1623 return str.substring(0, len); | |
1624 } | |
1625 | |
1626 /** | |
1627 * <p>Gets the rightmost <code>len</code> characters of a String.</p> | |
1628 * <p/> | |
1629 * <p>If <code>len</code> characters are not available, or the String | |
1630 * is <code>null</code>, the String will be returned without an | |
1631 * an exception. An exception is thrown if len is negative.</p> | |
1632 * <p/> | |
1633 * <pre> | |
1634 * StringUtils.right(null, *) = null | |
1635 * StringUtils.right(*, -ve) = "" | |
1636 * StringUtils.right("", *) = "" | |
1637 * StringUtils.right("abc", 0) = "" | |
1638 * StringUtils.right("abc", 2) = "bc" | |
1639 * StringUtils.right("abc", 4) = "abc" | |
1640 * </pre> | |
1641 * | |
1642 * @param str the String to get the rightmost characters from, may be null | |
1643 * @param len the length of the required String, must be zero or positive | |
1644 * @return the rightmost characters, <code>null</code> if null String input | |
1645 */ | |
1646 public static String right(String str, int len) | |
1647 { | |
1648 if (str == null) | |
1649 { | |
1650 return null; | |
1651 } | |
1652 if (len < 0) | |
1653 { | |
1654 return EMPTY; | |
1655 } | |
1656 if (str.length() <= len) | |
1657 { | |
1658 return str; | |
1659 } | |
1660 return str.substring(str.length() - len); | |
1661 } | |
1662 | |
1663 /** | |
1664 * <p>Gets <code>len</code> characters from the middle of a String.</p> | |
1665 * <p/> | |
1666 * <p>If <code>len</code> characters are not available, the remainder | |
1667 * of the String will be returned without an exception. If the | |
1668 * String is <code>null</code>, <code>null</code> will be returned. | |
1669 * An exception is thrown if len is negative.</p> | |
1670 * <p/> | |
1671 * <pre> | |
1672 * StringUtils.mid(null, *, *) = null | |
1673 * StringUtils.mid(*, *, -ve) = "" | |
1674 * StringUtils.mid("", 0, *) = "" | |
1675 * StringUtils.mid("abc", 0, 2) = "ab" | |
1676 * StringUtils.mid("abc", 0, 4) = "abc" | |
1677 * StringUtils.mid("abc", 2, 4) = "c" | |
1678 * StringUtils.mid("abc", 4, 2) = "" | |
1679 * StringUtils.mid("abc", -2, 2) = "ab" | |
1680 * </pre> | |
1681 * | |
1682 * @param str the String to get the characters from, may be null | |
1683 * @param pos the position to start from, negative treated as zero | |
1684 * @param len the length of the required String, must be zero or positive | |
1685 * @return the middle characters, <code>null</code> if null String input | |
1686 */ | |
1687 public static String mid(String str, int pos, int len) | |
1688 { | |
1689 if (str == null) | |
1690 { | |
1691 return null; | |
1692 } | |
1693 if (len < 0 || pos > str.length()) | |
1694 { | |
1695 return EMPTY; | |
1696 } | |
1697 if (pos < 0) | |
1698 { | |
1699 pos = 0; | |
1700 } | |
1701 if (str.length() <= (pos + len)) | |
1702 { | |
1703 return str.substring(pos); | |
1704 } | |
1705 return str.substring(pos, pos + len); | |
1706 } | |
1707 | |
1708 // SubStringAfter/SubStringBefore | |
1709 //----------------------------------------------------------------------- | |
1710 | |
1711 /** | |
1712 * <p>Gets the substring before the first occurrence of a separator. | |
1713 * The separator is not returned.</p> | |
1714 * <p/> | |
1715 * <p>A <code>null</code> string input will return <code>null</code>. | |
1716 * An empty ("") string input will return the empty string. | |
1717 * A <code>null</code> separator will return the input string.</p> | |
1718 * <p/> | |
1719 * <pre> | |
1720 * StringUtils.substringBefore(null, *) = null | |
1721 * StringUtils.substringBefore("", *) = "" | |
1722 * StringUtils.substringBefore("abc", "a") = "" | |
1723 * StringUtils.substringBefore("abcba", "b") = "a" | |
1724 * StringUtils.substringBefore("abc", "c") = "ab" | |
1725 * StringUtils.substringBefore("abc", "d") = "abc" | |
1726 * StringUtils.substringBefore("abc", "") = "" | |
1727 * StringUtils.substringBefore("abc", null) = "abc" | |
1728 * </pre> | |
1729 * | |
1730 * @param str the String to get a substring from, may be null | |
1731 * @param separator the String to search for, may be null | |
1732 * @return the substring before the first occurrence of the separator, | |
1733 * <code>null</code> if null String input | |
1734 * @since 2.0 | |
1735 */ | |
1736 public static String substringBefore(String str, String separator) | |
1737 { | |
1738 if (isEmpty(str) || separator == null) | |
1739 { | |
1740 return str; | |
1741 } | |
1742 if (separator.length() == 0) | |
1743 { | |
1744 return EMPTY; | |
1745 } | |
1746 int pos = str.indexOf(separator); | |
1747 if (pos == -1) | |
1748 { | |
1749 return str; | |
1750 } | |
1751 return str.substring(0, pos); | |
1752 } | |
1753 | |
1754 /** | |
1755 * <p>Gets the substring after the first occurrence of a separator. | |
1756 * The separator is not returned.</p> | |
1757 * <p/> | |
1758 * <p>A <code>null</code> string input will return <code>null</code>. | |
1759 * An empty ("") string input will return the empty string. | |
1760 * A <code>null</code> separator will return the empty string if the | |
1761 * input string is not <code>null</code>.</p> | |
1762 * <p/> | |
1763 * <pre> | |
1764 * StringUtils.substringAfter(null, *) = null | |
1765 * StringUtils.substringAfter("", *) = "" | |
1766 * StringUtils.substringAfter(*, null) = "" | |
1767 * StringUtils.substringAfter("abc", "a") = "bc" | |
1768 * StringUtils.substringAfter("abcba", "b") = "cba" | |
1769 * StringUtils.substringAfter("abc", "c") = "" | |
1770 * StringUtils.substringAfter("abc", "d") = "" | |
1771 * StringUtils.substringAfter("abc", "") = "abc" | |
1772 * </pre> | |
1773 * | |
1774 * @param str the String to get a substring from, may be null | |
1775 * @param separator the String to search for, may be null | |
1776 * @return the substring after the first occurrence of the separator, | |
1777 * <code>null</code> if null String input | |
1778 * @since 2.0 | |
1779 */ | |
1780 public static String substringAfter(String str, String separator) | |
1781 { | |
1782 if (isEmpty(str)) | |
1783 { | |
1784 return str; | |
1785 } | |
1786 if (separator == null) | |
1787 { | |
1788 return EMPTY; | |
1789 } | |
1790 int pos = str.indexOf(separator); | |
1791 if (pos == -1) | |
1792 { | |
1793 return EMPTY; | |
1794 } | |
1795 return str.substring(pos + separator.length()); | |
1796 } | |
1797 | |
1798 /** | |
1799 * <p>Gets the substring before the last occurrence of a separator. | |
1800 * The separator is not returned.</p> | |
1801 * <p/> | |
1802 * <p>A <code>null</code> string input will return <code>null</code>. | |
1803 * An empty ("") string input will return the empty string. | |
1804 * An empty or <code>null</code> separator will return the input string.</p> | |
1805 * <p/> | |
1806 * <pre> | |
1807 * StringUtils.substringBeforeLast(null, *) = null | |
1808 * StringUtils.substringBeforeLast("", *) = "" | |
1809 * StringUtils.substringBeforeLast("abcba", "b") = "abc" | |
1810 * StringUtils.substringBeforeLast("abc", "c") = "ab" | |
1811 * StringUtils.substringBeforeLast("a", "a") = "" | |
1812 * StringUtils.substringBeforeLast("a", "z") = "a" | |
1813 * StringUtils.substringBeforeLast("a", null) = "a" | |
1814 * StringUtils.substringBeforeLast("a", "") = "a" | |
1815 * </pre> | |
1816 * | |
1817 * @param str the String to get a substring from, may be null | |
1818 * @param separator the String to search for, may be null | |
1819 * @return the substring before the last occurrence of the separator, | |
1820 * <code>null</code> if null String input | |
1821 * @since 2.0 | |
1822 */ | |
1823 public static String substringBeforeLast(String str, String separator) | |
1824 { | |
1825 if (isEmpty(str) || isEmpty(separator)) | |
1826 { | |
1827 return str; | |
1828 } | |
1829 int pos = str.lastIndexOf(separator); | |
1830 if (pos == -1) | |
1831 { | |
1832 return str; | |
1833 } | |
1834 return str.substring(0, pos); | |
1835 } | |
1836 | |
1837 /** | |
1838 * <p>Gets the substring after the last occurrence of a separator. | |
1839 * The separator is not returned.</p> | |
1840 * <p/> | |
1841 * <p>A <code>null</code> string input will return <code>null</code>. | |
1842 * An empty ("") string input will return the empty string. | |
1843 * An empty or <code>null</code> separator will return the empty string if | |
1844 * the input string is not <code>null</code>.</p> | |
1845 * <p/> | |
1846 * <pre> | |
1847 * StringUtils.substringAfterLast(null, *) = null | |
1848 * StringUtils.substringAfterLast("", *) = "" | |
1849 * StringUtils.substringAfterLast(*, "") = "" | |
1850 * StringUtils.substringAfterLast(*, null) = "" | |
1851 * StringUtils.substringAfterLast("abc", "a") = "bc" | |
1852 * StringUtils.substringAfterLast("abcba", "b") = "a" | |
1853 * StringUtils.substringAfterLast("abc", "c") = "" | |
1854 * StringUtils.substringAfterLast("a", "a") = "" | |
1855 * StringUtils.substringAfterLast("a", "z") = "" | |
1856 * </pre> | |
1857 * | |
1858 * @param str the String to get a substring from, may be null | |
1859 * @param separator the String to search for, may be null | |
1860 * @return the substring after the last occurrence of the separator, | |
1861 * <code>null</code> if null String input | |
1862 * @since 2.0 | |
1863 */ | |
1864 public static String substringAfterLast(String str, String separator) | |
1865 { | |
1866 if (isEmpty(str)) | |
1867 { | |
1868 return str; | |
1869 } | |
1870 if (isEmpty(separator)) | |
1871 { | |
1872 return EMPTY; | |
1873 } | |
1874 int pos = str.lastIndexOf(separator); | |
1875 if (pos == -1 || pos == (str.length() - separator.length())) | |
1876 { | |
1877 return EMPTY; | |
1878 } | |
1879 return str.substring(pos + separator.length()); | |
1880 } | |
1881 | |
1882 // Substring between | |
1883 //----------------------------------------------------------------------- | |
1884 | |
1885 /** | |
1886 * <p>Gets the String that is nested in between two instances of the | |
1887 * same String.</p> | |
1888 * <p/> | |
1889 * <p>A <code>null</code> input String returns <code>null</code>. | |
1890 * A <code>null</code> tag returns <code>null</code>.</p> | |
1891 * <p/> | |
1892 * <pre> | |
1893 * StringUtils.substringBetween(null, *) = null | |
1894 * StringUtils.substringBetween("", "") = "" | |
1895 * StringUtils.substringBetween("", "tag") = null | |
1896 * StringUtils.substringBetween("tagabctag", null) = null | |
1897 * StringUtils.substringBetween("tagabctag", "") = "" | |
1898 * StringUtils.substringBetween("tagabctag", "tag") = "abc" | |
1899 * </pre> | |
1900 * | |
1901 * @param str the String containing the substring, may be null | |
1902 * @param tag the String before and after the substring, may be null | |
1903 * @return the substring, <code>null</code> if no match | |
1904 * @since 2.0 | |
1905 */ | |
1906 public static String substringBetween(String str, String tag) | |
1907 { | |
1908 return substringBetween(str, tag, tag); | |
1909 } | |
1910 | |
1911 /** | |
1912 * <p>Gets the String that is nested in between two Strings. | |
1913 * Only the first match is returned.</p> | |
1914 * <p/> | |
1915 * <p>A <code>null</code> input String returns <code>null</code>. | |
1916 * A <code>null</code> open/close returns <code>null</code> (no match). | |
1917 * An empty ("") open and close returns an empty string.</p> | |
1918 * <p/> | |
1919 * <pre> | |
1920 * StringUtils.substringBetween("wx[b]yz", "[", "]") = "b" | |
1921 * StringUtils.substringBetween(null, *, *) = null | |
1922 * StringUtils.substringBetween(*, null, *) = null | |
1923 * StringUtils.substringBetween(*, *, null) = null | |
1924 * StringUtils.substringBetween("", "", "") = "" | |
1925 * StringUtils.substringBetween("", "", "]") = null | |
1926 * StringUtils.substringBetween("", "[", "]") = null | |
1927 * StringUtils.substringBetween("yabcz", "", "") = "" | |
1928 * StringUtils.substringBetween("yabcz", "y", "z") = "abc" | |
1929 * StringUtils.substringBetween("yabczyabcz", "y", "z") = "abc" | |
1930 * </pre> | |
1931 * | |
1932 * @param str the String containing the substring, may be null | |
1933 * @param open the String before the substring, may be null | |
1934 * @param close the String after the substring, may be null | |
1935 * @return the substring, <code>null</code> if no match | |
1936 * @since 2.0 | |
1937 */ | |
1938 public static String substringBetween(String str, String open, String close) | |
1939 { | |
1940 if (str == null || open == null || close == null) | |
1941 { | |
1942 return null; | |
1943 } | |
1944 int start = str.indexOf(open); | |
1945 if (start != -1) | |
1946 { | |
1947 int end = str.indexOf(close, start + open.length()); | |
1948 if (end != -1) | |
1949 { | |
1950 return str.substring(start + open.length(), end); | |
1951 } | |
1952 } | |
1953 return null; | |
1954 } | |
1955 | |
1956 // Joining | |
1957 //----------------------------------------------------------------------- | |
1958 | |
1959 /** | |
1960 * <p>Concatenates elements of an array into a single String. | |
1961 * Null objects or empty strings within the array are represented by | |
1962 * empty strings.</p> | |
1963 * <p/> | |
1964 * <pre> | |
1965 * StringUtils.concatenate(null) = null | |
1966 * StringUtils.concatenate([]) = "" | |
1967 * StringUtils.concatenate([null]) = "" | |
1968 * StringUtils.concatenate(["a", "b", "c"]) = "abc" | |
1969 * StringUtils.concatenate([null, "", "a"]) = "a" | |
1970 * </pre> | |
1971 * | |
1972 * @param array the array of values to concatenate, may be null | |
1973 * @return the concatenated String, <code>null</code> if null array input | |
1974 * @deprecated Use the better named {@link #join(Object[])} instead. | |
1975 * Method will be removed in Commons Lang 3.0. | |
1976 */ | |
1977 public static String concatenate(Object[] array) | |
1978 { | |
1979 return join(array, null); | |
1980 } | |
1981 | |
1982 /** | |
1983 * <p>Joins the elements of the provided array into a single String | |
1984 * containing the provided list of elements.</p> | |
1985 * <p/> | |
1986 * <p>No separator is added to the joined String. | |
1987 * Null objects or empty strings within the array are represented by | |
1988 * empty strings.</p> | |
1989 * <p/> | |
1990 * <pre> | |
1991 * StringUtils.join(null) = null | |
1992 * StringUtils.join([]) = "" | |
1993 * StringUtils.join([null]) = "" | |
1994 * StringUtils.join(["a", "b", "c"]) = "abc" | |
1995 * StringUtils.join([null, "", "a"]) = "a" | |
1996 * </pre> | |
1997 * | |
1998 * @param array the array of values to join together, may be null | |
1999 * @return the joined String, <code>null</code> if null array input | |
2000 * @since 2.0 | |
2001 */ | |
2002 public static String join(Object[] array) | |
2003 { | |
2004 return join(array, null); | |
2005 } | |
2006 | |
2007 /** | |
2008 * <p>Joins the elements of the provided array into a single String | |
2009 * containing the provided list of elements.</p> | |
2010 * <p/> | |
2011 * <p>No delimiter is added before or after the list. | |
2012 * Null objects or empty strings within the array are represented by | |
2013 * empty strings.</p> | |
2014 * <p/> | |
2015 * <pre> | |
2016 * StringUtils.join(null, *) = null | |
2017 * StringUtils.join([], *) = "" | |
2018 * StringUtils.join([null], *) = "" | |
2019 * StringUtils.join(["a", "b", "c"], ';') = "a;b;c" | |
2020 * StringUtils.join(["a", "b", "c"], null) = "abc" | |
2021 * StringUtils.join([null, "", "a"], ';') = ";;a" | |
2022 * </pre> | |
2023 * | |
2024 * @param array the array of values to join together, may be null | |
2025 * @param separator the separator character to use | |
2026 * @return the joined String, <code>null</code> if null array input | |
2027 * @since 2.0 | |
2028 */ | |
2029 public static String join(Object[] array, char separator) | |
2030 { | |
2031 if (array == null) | |
2032 { | |
2033 return null; | |
2034 } | |
2035 | |
2036 return join(array, separator, 0, array.length); | |
2037 } | |
2038 | |
2039 /** | |
2040 * <p>Joins the elements of the provided array into a single String | |
2041 * containing the provided list of elements.</p> | |
2042 * <p/> | |
2043 * <p>No delimiter is added before or after the list. | |
2044 * Null objects or empty strings within the array are represented by | |
2045 * empty strings.</p> | |
2046 * <p/> | |
2047 * <pre> | |
2048 * StringUtils.join(null, *) = null | |
2049 * StringUtils.join([], *) = "" | |
2050 * StringUtils.join([null], *) = "" | |
2051 * StringUtils.join(["a", "b", "c"], ';') = "a;b;c" | |
2052 * StringUtils.join(["a", "b", "c"], null) = "abc" | |
2053 * StringUtils.join([null, "", "a"], ';') = ";;a" | |
2054 * </pre> | |
2055 * | |
2056 * @param array the array of values to join together, may be null | |
2057 * @param separator the separator character to use | |
2058 * @param startIndex the first index to start joining from. It is | |
2059 * an error to pass in an end index past the end of the arra
y | |
2060 * @param endIndex the index to stop joining from (exclusive). It is | |
2061 * an error to pass in an end index past the end of the arra
y | |
2062 * @return the joined String, <code>null</code> if null array input | |
2063 * @since 2.0 | |
2064 */ | |
2065 public static String join(Object[] array, char separator, int startIndex, int
endIndex) | |
2066 { | |
2067 if (array == null) | |
2068 { | |
2069 return null; | |
2070 } | |
2071 int bufSize = (endIndex - startIndex); | |
2072 if (bufSize <= 0) | |
2073 { | |
2074 return EMPTY; | |
2075 } | |
2076 | |
2077 bufSize *= ((array[startIndex] == null ? 16 : array[startIndex].toString().l
ength()) + 1); | |
2078 StringBuffer buf = new StringBuffer(bufSize); | |
2079 | |
2080 for (int i = startIndex; i < endIndex; i++) | |
2081 { | |
2082 if (i > startIndex) | |
2083 { | |
2084 buf.append(separator); | |
2085 } | |
2086 if (array[i] != null) | |
2087 { | |
2088 buf.append(array[i]); | |
2089 } | |
2090 } | |
2091 return buf.toString(); | |
2092 } | |
2093 | |
2094 | |
2095 /** | |
2096 * <p>Joins the elements of the provided array into a single String | |
2097 * containing the provided list of elements.</p> | |
2098 * <p/> | |
2099 * <p>No delimiter is added before or after the list. | |
2100 * A <code>null</code> separator is the same as an empty String (""). | |
2101 * Null objects or empty strings within the array are represented by | |
2102 * empty strings.</p> | |
2103 * <p/> | |
2104 * <pre> | |
2105 * StringUtils.join(null, *) = null | |
2106 * StringUtils.join([], *) = "" | |
2107 * StringUtils.join([null], *) = "" | |
2108 * StringUtils.join(["a", "b", "c"], "--") = "a--b--c" | |
2109 * StringUtils.join(["a", "b", "c"], null) = "abc" | |
2110 * StringUtils.join(["a", "b", "c"], "") = "abc" | |
2111 * StringUtils.join([null, "", "a"], ',') = ",,a" | |
2112 * </pre> | |
2113 * | |
2114 * @param array the array of values to join together, may be null | |
2115 * @param separator the separator character to use, null treated as "" | |
2116 * @return the joined String, <code>null</code> if null array input | |
2117 */ | |
2118 public static String join(Object[] array, String separator) | |
2119 { | |
2120 if (array == null) | |
2121 { | |
2122 return null; | |
2123 } | |
2124 return join(array, separator, 0, array.length); | |
2125 } | |
2126 | |
2127 /** | |
2128 * <p>Joins the elements of the provided array into a single String | |
2129 * containing the provided list of elements.</p> | |
2130 * <p/> | |
2131 * <p>No delimiter is added before or after the list. | |
2132 * A <code>null</code> separator is the same as an empty String (""). | |
2133 * Null objects or empty strings within the array are represented by | |
2134 * empty strings.</p> | |
2135 * <p/> | |
2136 * <pre> | |
2137 * StringUtils.join(null, *) = null | |
2138 * StringUtils.join([], *) = "" | |
2139 * StringUtils.join([null], *) = "" | |
2140 * StringUtils.join(["a", "b", "c"], "--") = "a--b--c" | |
2141 * StringUtils.join(["a", "b", "c"], null) = "abc" | |
2142 * StringUtils.join(["a", "b", "c"], "") = "abc" | |
2143 * StringUtils.join([null, "", "a"], ',') = ",,a" | |
2144 * </pre> | |
2145 * | |
2146 * @param array the array of values to join together, may be null | |
2147 * @param separator the separator character to use, null treated as "" | |
2148 * @param startIndex the first index to start joining from. It is | |
2149 * an error to pass in an end index past the end of the arra
y | |
2150 * @param endIndex the index to stop joining from (exclusive). It is | |
2151 * an error to pass in an end index past the end of the arra
y | |
2152 * @return the joined String, <code>null</code> if null array input | |
2153 */ | |
2154 public static String join(Object[] array, String separator, int startIndex, in
t endIndex) | |
2155 { | |
2156 if (array == null) | |
2157 { | |
2158 return null; | |
2159 } | |
2160 if (separator == null) | |
2161 { | |
2162 separator = EMPTY; | |
2163 } | |
2164 | |
2165 // endIndex - startIndex > 0: Len = NofStrings *(len(firstString) + len(se
parator)) | |
2166 // (Assuming that all Strings are roughly equally long) | |
2167 int bufSize = (endIndex - startIndex); | |
2168 if (bufSize <= 0) | |
2169 { | |
2170 return EMPTY; | |
2171 } | |
2172 | |
2173 bufSize *= ((array[startIndex] == null ? 16 : array[startIndex].toString().l
ength()) | |
2174 + separator.length()); | |
2175 | |
2176 StringBuffer buf = new StringBuffer(bufSize); | |
2177 | |
2178 for (int i = startIndex; i < endIndex; i++) | |
2179 { | |
2180 if (i > startIndex) | |
2181 { | |
2182 buf.append(separator); | |
2183 } | |
2184 if (array[i] != null) | |
2185 { | |
2186 buf.append(array[i]); | |
2187 } | |
2188 } | |
2189 return buf.toString(); | |
2190 } | |
2191 | |
2192 // Delete | |
2193 //----------------------------------------------------------------------- | |
2194 | |
2195 /** | |
2196 * <p>Deletes all whitespaces from a String as defined by | |
2197 * {@link Character#isWhitespace(char)}.</p> | |
2198 * <p/> | |
2199 * <pre> | |
2200 * StringUtils.deleteWhitespace(null) = null | |
2201 * StringUtils.deleteWhitespace("") = "" | |
2202 * StringUtils.deleteWhitespace("abc") = "abc" | |
2203 * StringUtils.deleteWhitespace(" ab c ") = "abc" | |
2204 * </pre> | |
2205 * | |
2206 * @param str the String to delete whitespace from, may be null | |
2207 * @return the String without whitespaces, <code>null</code> if null String in
put | |
2208 */ | |
2209 public static String deleteWhitespace(String str) | |
2210 { | |
2211 if (isEmpty(str)) | |
2212 { | |
2213 return str; | |
2214 } | |
2215 int sz = str.length(); | |
2216 char[] chs = new char[sz]; | |
2217 int count = 0; | |
2218 for (int i = 0; i < sz; i++) | |
2219 { | |
2220 if (!Character.isWhitespace(str.charAt(i))) | |
2221 { | |
2222 chs[count++] = str.charAt(i); | |
2223 } | |
2224 } | |
2225 if (count == sz) | |
2226 { | |
2227 return str; | |
2228 } | |
2229 return new String(chs, 0, count); | |
2230 } | |
2231 | |
2232 // Remove | |
2233 //----------------------------------------------------------------------- | |
2234 | |
2235 /** | |
2236 * <p>Removes a substring only if it is at the begining of a source string, | |
2237 * otherwise returns the source string.</p> | |
2238 * <p/> | |
2239 * <p>A <code>null</code> source string will return <code>null</code>. | |
2240 * An empty ("") source string will return the empty string. | |
2241 * A <code>null</code> search string will return the source string.</p> | |
2242 * <p/> | |
2243 * <pre> | |
2244 * StringUtils.removeStart(null, *) = null | |
2245 * StringUtils.removeStart("", *) = "" | |
2246 * StringUtils.removeStart(*, null) = * | |
2247 * StringUtils.removeStart("www.domain.com", "www.") = "domain.com" | |
2248 * StringUtils.removeStart("domain.com", "www.") = "domain.com" | |
2249 * StringUtils.removeStart("www.domain.com", "domain") = "www.domain.com" | |
2250 * StringUtils.removeStart("abc", "") = "abc" | |
2251 * </pre> | |
2252 * | |
2253 * @param str the source String to search, may be null | |
2254 * @param remove the String to search for and remove, may be null | |
2255 * @return the substring with the string removed if found, | |
2256 * <code>null</code> if null String input | |
2257 * @since 2.1 | |
2258 */ | |
2259 public static String removeStart(String str, String remove) | |
2260 { | |
2261 if (isEmpty(str) || isEmpty(remove)) | |
2262 { | |
2263 return str; | |
2264 } | |
2265 if (str.startsWith(remove)) | |
2266 { | |
2267 return str.substring(remove.length()); | |
2268 } | |
2269 return str; | |
2270 } | |
2271 | |
2272 /** | |
2273 * <p>Case insensitive removal of a substring if it is at the begining of a so
urce string, | |
2274 * otherwise returns the source string.</p> | |
2275 * <p/> | |
2276 * <p>A <code>null</code> source string will return <code>null</code>. | |
2277 * An empty ("") source string will return the empty string. | |
2278 * A <code>null</code> search string will return the source string.</p> | |
2279 * <p/> | |
2280 * <pre> | |
2281 * StringUtils.removeStartIgnoreCase(null, *) = null | |
2282 * StringUtils.removeStartIgnoreCase("", *) = "" | |
2283 * StringUtils.removeStartIgnoreCase(*, null) = * | |
2284 * StringUtils.removeStartIgnoreCase("www.domain.com", "www.") = "domain.com
" | |
2285 * StringUtils.removeStartIgnoreCase("www.domain.com", "WWW.") = "domain.com
" | |
2286 * StringUtils.removeStartIgnoreCase("domain.com", "www.") = "domain.com
" | |
2287 * StringUtils.removeStartIgnoreCase("www.domain.com", "domain") = "www.domain
.com" | |
2288 * StringUtils.removeStartIgnoreCase("abc", "") = "abc" | |
2289 * </pre> | |
2290 * | |
2291 * @param str the source String to search, may be null | |
2292 * @param remove the String to search for (case insensitive) and remove, may b
e null | |
2293 * @return the substring with the string removed if found, | |
2294 * <code>null</code> if null String input | |
2295 * @since 2.4 | |
2296 */ | |
2297 public static String removeStartIgnoreCase(String str, String remove) | |
2298 { | |
2299 if (isEmpty(str) || isEmpty(remove)) | |
2300 { | |
2301 return str; | |
2302 } | |
2303 if (startsWithIgnoreCase(str, remove)) | |
2304 { | |
2305 return str.substring(remove.length()); | |
2306 } | |
2307 return str; | |
2308 } | |
2309 | |
2310 /** | |
2311 * <p>Removes a substring only if it is at the end of a source string, | |
2312 * otherwise returns the source string.</p> | |
2313 * <p/> | |
2314 * <p>A <code>null</code> source string will return <code>null</code>. | |
2315 * An empty ("") source string will return the empty string. | |
2316 * A <code>null</code> search string will return the source string.</p> | |
2317 * <p/> | |
2318 * <pre> | |
2319 * StringUtils.removeEnd(null, *) = null | |
2320 * StringUtils.removeEnd("", *) = "" | |
2321 * StringUtils.removeEnd(*, null) = * | |
2322 * StringUtils.removeEnd("www.domain.com", ".com.") = "www.domain.com" | |
2323 * StringUtils.removeEnd("www.domain.com", ".com") = "www.domain" | |
2324 * StringUtils.removeEnd("www.domain.com", "domain") = "www.domain.com" | |
2325 * StringUtils.removeEnd("abc", "") = "abc" | |
2326 * </pre> | |
2327 * | |
2328 * @param str the source String to search, may be null | |
2329 * @param remove the String to search for and remove, may be null | |
2330 * @return the substring with the string removed if found, | |
2331 * <code>null</code> if null String input | |
2332 * @since 2.1 | |
2333 */ | |
2334 public static String removeEnd(String str, String remove) | |
2335 { | |
2336 if (isEmpty(str) || isEmpty(remove)) | |
2337 { | |
2338 return str; | |
2339 } | |
2340 if (str.endsWith(remove)) | |
2341 { | |
2342 return str.substring(0, str.length() - remove.length()); | |
2343 } | |
2344 return str; | |
2345 } | |
2346 | |
2347 /** | |
2348 * <p>Case insensitive removal of a substring if it is at the end of a source
string, | |
2349 * otherwise returns the source string.</p> | |
2350 * <p/> | |
2351 * <p>A <code>null</code> source string will return <code>null</code>. | |
2352 * An empty ("") source string will return the empty string. | |
2353 * A <code>null</code> search string will return the source string.</p> | |
2354 * <p/> | |
2355 * <pre> | |
2356 * StringUtils.removeEnd(null, *) = null | |
2357 * StringUtils.removeEnd("", *) = "" | |
2358 * StringUtils.removeEnd(*, null) = * | |
2359 * StringUtils.removeEnd("www.domain.com", ".com.") = "www.domain.com." | |
2360 * StringUtils.removeEnd("www.domain.com", ".com") = "www.domain" | |
2361 * StringUtils.removeEnd("www.domain.com", "domain") = "www.domain.com" | |
2362 * StringUtils.removeEnd("abc", "") = "abc" | |
2363 * </pre> | |
2364 * | |
2365 * @param str the source String to search, may be null | |
2366 * @param remove the String to search for (case insensitive) and remove, may b
e null | |
2367 * @return the substring with the string removed if found, | |
2368 * <code>null</code> if null String input | |
2369 * @since 2.4 | |
2370 */ | |
2371 public static String removeEndIgnoreCase(String str, String remove) | |
2372 { | |
2373 if (isEmpty(str) || isEmpty(remove)) | |
2374 { | |
2375 return str; | |
2376 } | |
2377 if (endsWithIgnoreCase(str, remove)) | |
2378 { | |
2379 return str.substring(0, str.length() - remove.length()); | |
2380 } | |
2381 return str; | |
2382 } | |
2383 | |
2384 /** | |
2385 * <p>Removes all occurrences of a substring from within the source string.</p
> | |
2386 * <p/> | |
2387 * <p>A <code>null</code> source string will return <code>null</code>. | |
2388 * An empty ("") source string will return the empty string. | |
2389 * A <code>null</code> remove string will return the source string. | |
2390 * An empty ("") remove string will return the source string.</p> | |
2391 * <p/> | |
2392 * <pre> | |
2393 * StringUtils.remove(null, *) = null | |
2394 * StringUtils.remove("", *) = "" | |
2395 * StringUtils.remove(*, null) = * | |
2396 * StringUtils.remove(*, "") = * | |
2397 * StringUtils.remove("queued", "ue") = "qd" | |
2398 * StringUtils.remove("queued", "zz") = "queued" | |
2399 * </pre> | |
2400 * | |
2401 * @param str the source String to search, may be null | |
2402 * @param remove the String to search for and remove, may be null | |
2403 * @return the substring with the string removed if found, | |
2404 * <code>null</code> if null String input | |
2405 * @since 2.1 | |
2406 */ | |
2407 public static String remove(String str, String remove) | |
2408 { | |
2409 if (isEmpty(str) || isEmpty(remove)) | |
2410 { | |
2411 return str; | |
2412 } | |
2413 return replace(str, remove, EMPTY, -1); | |
2414 } | |
2415 | |
2416 /** | |
2417 * <p>Removes all occurrences of a character from within the source string.</p
> | |
2418 * <p/> | |
2419 * <p>A <code>null</code> source string will return <code>null</code>. | |
2420 * An empty ("") source string will return the empty string.</p> | |
2421 * <p/> | |
2422 * <pre> | |
2423 * StringUtils.remove(null, *) = null | |
2424 * StringUtils.remove("", *) = "" | |
2425 * StringUtils.remove("queued", 'u') = "qeed" | |
2426 * StringUtils.remove("queued", 'z') = "queued" | |
2427 * </pre> | |
2428 * | |
2429 * @param str the source String to search, may be null | |
2430 * @param remove the char to search for and remove, may be null | |
2431 * @return the substring with the char removed if found, | |
2432 * <code>null</code> if null String input | |
2433 * @since 2.1 | |
2434 */ | |
2435 public static String remove(String str, char remove) | |
2436 { | |
2437 if (isEmpty(str) || str.indexOf(remove) == -1) | |
2438 { | |
2439 return str; | |
2440 } | |
2441 char[] chars = str.toCharArray(); | |
2442 int pos = 0; | |
2443 for (int i = 0; i < chars.length; i++) | |
2444 { | |
2445 if (chars[i] != remove) | |
2446 { | |
2447 chars[pos++] = chars[i]; | |
2448 } | |
2449 } | |
2450 return new String(chars, 0, pos); | |
2451 } | |
2452 | |
2453 // Replacing | |
2454 //----------------------------------------------------------------------- | |
2455 | |
2456 /** | |
2457 * <p>Replaces a String with another String inside a larger String, once.</p> | |
2458 * <p/> | |
2459 * <p>A <code>null</code> reference passed to this method is a no-op.</p> | |
2460 * <p/> | |
2461 * <pre> | |
2462 * StringUtils.replaceOnce(null, *, *) = null | |
2463 * StringUtils.replaceOnce("", *, *) = "" | |
2464 * StringUtils.replaceOnce("any", null, *) = "any" | |
2465 * StringUtils.replaceOnce("any", *, null) = "any" | |
2466 * StringUtils.replaceOnce("any", "", *) = "any" | |
2467 * StringUtils.replaceOnce("aba", "a", null) = "aba" | |
2468 * StringUtils.replaceOnce("aba", "a", "") = "ba" | |
2469 * StringUtils.replaceOnce("aba", "a", "z") = "zba" | |
2470 * </pre> | |
2471 * | |
2472 * @param text text to search and replace in, may be null | |
2473 * @param searchString the String to search for, may be null | |
2474 * @param replacement the String to replace with, may be null | |
2475 * @return the text with any replacements processed, | |
2476 * <code>null</code> if null String input | |
2477 * @see #replace(String text, String searchString, String replacement, int max
) | |
2478 */ | |
2479 public static String replaceOnce(String text, String searchString, String repl
acement) | |
2480 { | |
2481 return replace(text, searchString, replacement, 1); | |
2482 } | |
2483 | |
2484 /** | |
2485 * <p>Replaces all occurrences of a String within another String.</p> | |
2486 * <p/> | |
2487 * <p>A <code>null</code> reference passed to this method is a no-op.</p> | |
2488 * <p/> | |
2489 * <pre> | |
2490 * StringUtils.replace(null, *, *) = null | |
2491 * StringUtils.replace("", *, *) = "" | |
2492 * StringUtils.replace("any", null, *) = "any" | |
2493 * StringUtils.replace("any", *, null) = "any" | |
2494 * StringUtils.replace("any", "", *) = "any" | |
2495 * StringUtils.replace("aba", "a", null) = "aba" | |
2496 * StringUtils.replace("aba", "a", "") = "b" | |
2497 * StringUtils.replace("aba", "a", "z") = "zbz" | |
2498 * </pre> | |
2499 * | |
2500 * @param text text to search and replace in, may be null | |
2501 * @param searchString the String to search for, may be null | |
2502 * @param replacement the String to replace it with, may be null | |
2503 * @return the text with any replacements processed, | |
2504 * <code>null</code> if null String input | |
2505 * @see #replace(String text, String searchString, String replacement, int max
) | |
2506 */ | |
2507 public static String replace(String text, String searchString, String replacem
ent) | |
2508 { | |
2509 return replace(text, searchString, replacement, -1); | |
2510 } | |
2511 | |
2512 /** | |
2513 * <p>Replaces a String with another String inside a larger String, | |
2514 * for the first <code>max</code> values of the search String.</p> | |
2515 * <p/> | |
2516 * <p>A <code>null</code> reference passed to this method is a no-op.</p> | |
2517 * <p/> | |
2518 * <pre> | |
2519 * StringUtils.replace(null, *, *, *) = null | |
2520 * StringUtils.replace("", *, *, *) = "" | |
2521 * StringUtils.replace("any", null, *, *) = "any" | |
2522 * StringUtils.replace("any", *, null, *) = "any" | |
2523 * StringUtils.replace("any", "", *, *) = "any" | |
2524 * StringUtils.replace("any", *, *, 0) = "any" | |
2525 * StringUtils.replace("abaa", "a", null, -1) = "abaa" | |
2526 * StringUtils.replace("abaa", "a", "", -1) = "b" | |
2527 * StringUtils.replace("abaa", "a", "z", 0) = "abaa" | |
2528 * StringUtils.replace("abaa", "a", "z", 1) = "zbaa" | |
2529 * StringUtils.replace("abaa", "a", "z", 2) = "zbza" | |
2530 * StringUtils.replace("abaa", "a", "z", -1) = "zbzz" | |
2531 * </pre> | |
2532 * | |
2533 * @param text text to search and replace in, may be null | |
2534 * @param searchString the String to search for, may be null | |
2535 * @param replacement the String to replace it with, may be null | |
2536 * @param max maximum number of values to replace, or <code>-1</code>
if no maximum | |
2537 * @return the text with any replacements processed, | |
2538 * <code>null</code> if null String input | |
2539 */ | |
2540 public static String replace(String text, String searchString, String replacem
ent, int max) | |
2541 { | |
2542 if (isEmpty(text) || isEmpty(searchString) || replacement == null || max ==
0) | |
2543 { | |
2544 return text; | |
2545 } | |
2546 int start = 0; | |
2547 int end = text.indexOf(searchString, start); | |
2548 if (end == -1) | |
2549 { | |
2550 return text; | |
2551 } | |
2552 int replLength = searchString.length(); | |
2553 int increase = replacement.length() - replLength; | |
2554 increase = (increase < 0 ? 0 : increase); | |
2555 increase *= (max < 0 ? 16 : (max > 64 ? 64 : max)); | |
2556 StringBuffer buf = new StringBuffer(text.length() + increase); | |
2557 while (end != -1) | |
2558 { | |
2559 buf.append(text.substring(start, end)).append(replacement); | |
2560 start = end + replLength; | |
2561 if (--max == 0) | |
2562 { | |
2563 break; | |
2564 } | |
2565 end = text.indexOf(searchString, start); | |
2566 } | |
2567 buf.append(text.substring(start)); | |
2568 return buf.toString(); | |
2569 } | |
2570 | |
2571 /** | |
2572 * <p> | |
2573 * Replaces all occurrences of Strings within another String. | |
2574 * </p> | |
2575 * <p/> | |
2576 * <p> | |
2577 * A <code>null</code> reference passed to this method is a no-op, or if | |
2578 * any "search string" or "string to replace" is null, that replace will be | |
2579 * ignored. This will not repeat. For repeating replaces, call the | |
2580 * overloaded method. | |
2581 * </p> | |
2582 * <p/> | |
2583 * <pre> | |
2584 * StringUtils.replaceEach(null, *, *) = null | |
2585 * StringUtils.replaceEach("", *, *) = "" | |
2586 * StringUtils.replaceEach("aba", null, null) = "aba" | |
2587 * StringUtils.replaceEach("aba", new String[0], null) = "aba" | |
2588 * StringUtils.replaceEach("aba", null, new String[0]) = "aba" | |
2589 * StringUtils.replaceEach("aba", new String[]{"a"}, null) = "aba" | |
2590 * StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}) = "b" | |
2591 * StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}) = "
aba" | |
2592 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w"
, "t"}) = "wcte" | |
2593 * (example of how it does not repeat) | |
2594 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "t"}) = "dcte" | |
2595 * </pre> | |
2596 * | |
2597 * @param text text to search and replace in, no-op if null | |
2598 * @param searchList the Strings to search for, no-op if null | |
2599 * @param replacementList the Strings to replace them with, no-op if null | |
2600 * @return the text with any replacements processed, <code>null</code> if | |
2601 * null String input | |
2602 * @throws IndexOutOfBoundsException if the lengths of the arrays are not the
same (null is ok, | |
2603 * and/or size 0) | |
2604 * @since 2.4 | |
2605 */ | |
2606 public static String replaceEach(String text, String[] searchList, String[] re
placementList) | |
2607 { | |
2608 return replaceEach(text, searchList, replacementList, false, 0); | |
2609 } | |
2610 | |
2611 /** | |
2612 * <p> | |
2613 * Replaces all occurrences of Strings within another String. | |
2614 * </p> | |
2615 * <p/> | |
2616 * <p> | |
2617 * A <code>null</code> reference passed to this method is a no-op, or if | |
2618 * any "search string" or "string to replace" is null, that replace will be | |
2619 * ignored. This will not repeat. For repeating replaces, call the | |
2620 * overloaded method. | |
2621 * </p> | |
2622 * <p/> | |
2623 * <pre> | |
2624 * StringUtils.replaceEach(null, *, *, *) = null | |
2625 * StringUtils.replaceEach("", *, *, *) = "" | |
2626 * StringUtils.replaceEach("aba", null, null, *) = "aba" | |
2627 * StringUtils.replaceEach("aba", new String[0], null, *) = "aba" | |
2628 * StringUtils.replaceEach("aba", null, new String[0], *) = "aba" | |
2629 * StringUtils.replaceEach("aba", new String[]{"a"}, null, *) = "aba" | |
2630 * StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}, *) = "
b" | |
2631 * StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}, *) =
"aba" | |
2632 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w"
, "t"}, *) = "wcte" | |
2633 * (example of how it repeats) | |
2634 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "t"}, false) = "dcte" | |
2635 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "t"}, true) = "tcte" | |
2636 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "ab"}, true) = IllegalArgumentException | |
2637 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "ab"}, false) = "dcabe" | |
2638 * </pre> | |
2639 * | |
2640 * @param text text to search and replace in, no-op if null | |
2641 * @param searchList the Strings to search for, no-op if null | |
2642 * @param replacementList the Strings to replace them with, no-op if null | |
2643 * @return the text with any replacements processed, <code>null</code> if | |
2644 * null String input | |
2645 * @throws IllegalArgumentException if the search is repeating and there is a
n endless loop due | |
2646 * to outputs of one being inputs to another | |
2647 * @throws IndexOutOfBoundsException if the lengths of the arrays are not the
same (null is ok, | |
2648 * and/or size 0) | |
2649 * @since 2.4 | |
2650 */ | |
2651 public static String replaceEachRepeatedly(String text, String[] searchList, S
tring[] replacementList) | |
2652 { | |
2653 // timeToLive should be 0 if not used or nothing to replace, else it's | |
2654 // the length of the replace array | |
2655 int timeToLive = searchList == null ? 0 : searchList.length; | |
2656 return replaceEach(text, searchList, replacementList, true, timeToLive); | |
2657 } | |
2658 | |
2659 /** | |
2660 * <p> | |
2661 * Replaces all occurrences of Strings within another String. | |
2662 * </p> | |
2663 * <p/> | |
2664 * <p> | |
2665 * A <code>null</code> reference passed to this method is a no-op, or if | |
2666 * any "search string" or "string to replace" is null, that replace will be | |
2667 * ignored. | |
2668 * </p> | |
2669 * <p/> | |
2670 * <pre> | |
2671 * StringUtils.replaceEach(null, *, *, *) = null | |
2672 * StringUtils.replaceEach("", *, *, *) = "" | |
2673 * StringUtils.replaceEach("aba", null, null, *) = "aba" | |
2674 * StringUtils.replaceEach("aba", new String[0], null, *) = "aba" | |
2675 * StringUtils.replaceEach("aba", null, new String[0], *) = "aba" | |
2676 * StringUtils.replaceEach("aba", new String[]{"a"}, null, *) = "aba" | |
2677 * StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}, *) = "
b" | |
2678 * StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}, *) =
"aba" | |
2679 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w"
, "t"}, *) = "wcte" | |
2680 * (example of how it repeats) | |
2681 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "t"}, false) = "dcte" | |
2682 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "t"}, true) = "tcte" | |
2683 * StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d"
, "ab"}, *) = IllegalArgumentException | |
2684 * </pre> | |
2685 * | |
2686 * @param text text to search and replace in, no-op if null | |
2687 * @param searchList the Strings to search for, no-op if null | |
2688 * @param replacementList the Strings to replace them with, no-op if null | |
2689 * @param repeat if true, then replace repeatedly | |
2690 * until there are no more possible replacements or tim
eToLive < 0 | |
2691 * @param timeToLive if less than 0 then there is a circular reference an
d endless | |
2692 * loop | |
2693 * @return the text with any replacements processed, <code>null</code> if | |
2694 * null String input | |
2695 * @throws IllegalArgumentException if the search is repeating and there is a
n endless loop due | |
2696 * to outputs of one being inputs to another | |
2697 * @throws IndexOutOfBoundsException if the lengths of the arrays are not the
same (null is ok, | |
2698 * and/or size 0) | |
2699 * @since 2.4 | |
2700 */ | |
2701 private static String replaceEach(String text, String[] searchList, String[] r
eplacementList, | |
2702 boolean repeat, int timeToLive) | |
2703 { | |
2704 | |
2705 // mchyzer Performance note: This creates very few new objects (one major go
al) | |
2706 // let me know if there are performance requests, we can create a harness to
measure | |
2707 | |
2708 if (text == null || text.length() == 0 || searchList == null || | |
2709 searchList.length == 0 || replacementList == null || replacementList.lengt
h == 0) | |
2710 { | |
2711 return text; | |
2712 } | |
2713 | |
2714 // if recursing, this shouldnt be less than 0 | |
2715 if (timeToLive < 0) | |
2716 { | |
2717 throw new IllegalStateException("TimeToLive of " + timeToLive + " is less
than 0: " + text); | |
2718 } | |
2719 | |
2720 int searchLength = searchList.length; | |
2721 int replacementLength = replacementList.length; | |
2722 | |
2723 // make sure lengths are ok, these need to be equal | |
2724 if (searchLength != replacementLength) | |
2725 { | |
2726 throw new IllegalArgumentException("Search and Replace array lengths don't
match: " | |
2727 + searchLength | |
2728 + " vs " | |
2729 + replacementLength); | |
2730 } | |
2731 | |
2732 // keep track of which still have matches | |
2733 boolean[] noMoreMatchesForReplIndex = new boolean[searchLength]; | |
2734 | |
2735 // index on index that the match was found | |
2736 int textIndex = -1; | |
2737 int replaceIndex = -1; | |
2738 int tempIndex = -1; | |
2739 | |
2740 // index of replace array that will replace the search string found | |
2741 // NOTE: logic duplicated below START | |
2742 for (int i = 0; i < searchLength; i++) | |
2743 { | |
2744 if (noMoreMatchesForReplIndex[i] || searchList[i] == null || | |
2745 searchList[i].length() == 0 || replacementList[i] == null) | |
2746 { | |
2747 continue; | |
2748 } | |
2749 tempIndex = text.indexOf(searchList[i]); | |
2750 | |
2751 // see if we need to keep searching for this | |
2752 if (tempIndex == -1) | |
2753 { | |
2754 noMoreMatchesForReplIndex[i] = true; | |
2755 } else | |
2756 { | |
2757 if (textIndex == -1 || tempIndex < textIndex) | |
2758 { | |
2759 textIndex = tempIndex; | |
2760 replaceIndex = i; | |
2761 } | |
2762 } | |
2763 } | |
2764 // NOTE: logic mostly below END | |
2765 | |
2766 // no search strings found, we are done | |
2767 if (textIndex == -1) | |
2768 { | |
2769 return text; | |
2770 } | |
2771 | |
2772 int start = 0; | |
2773 | |
2774 // get a good guess on the size of the result buffer so it doesnt have to do
uble if it goes over a bit | |
2775 int increase = 0; | |
2776 | |
2777 // count the replacement text elements that are larger than their correspond
ing text being replaced | |
2778 for (int i = 0; i < searchList.length; i++) | |
2779 { | |
2780 int greater = replacementList[i].length() - searchList[i].length(); | |
2781 if (greater > 0) | |
2782 { | |
2783 increase += 3 * greater; // assume 3 matches | |
2784 } | |
2785 } | |
2786 // have upper-bound at 20% increase, then let Java take over | |
2787 increase = Math.min(increase, text.length() / 5); | |
2788 | |
2789 StringBuffer buf = new StringBuffer(text.length() + increase); | |
2790 | |
2791 while (textIndex != -1) | |
2792 { | |
2793 | |
2794 for (int i = start; i < textIndex; i++) | |
2795 { | |
2796 buf.append(text.charAt(i)); | |
2797 } | |
2798 buf.append(replacementList[replaceIndex]); | |
2799 | |
2800 start = textIndex + searchList[replaceIndex].length(); | |
2801 | |
2802 textIndex = -1; | |
2803 replaceIndex = -1; | |
2804 tempIndex = -1; | |
2805 // find the next earliest match | |
2806 // NOTE: logic mostly duplicated above START | |
2807 for (int i = 0; i < searchLength; i++) | |
2808 { | |
2809 if (noMoreMatchesForReplIndex[i] || searchList[i] == null || | |
2810 searchList[i].length() == 0 || replacementList[i] == null) | |
2811 { | |
2812 continue; | |
2813 } | |
2814 tempIndex = text.indexOf(searchList[i], start); | |
2815 | |
2816 // see if we need to keep searching for this | |
2817 if (tempIndex == -1) | |
2818 { | |
2819 noMoreMatchesForReplIndex[i] = true; | |
2820 } else | |
2821 { | |
2822 if (textIndex == -1 || tempIndex < textIndex) | |
2823 { | |
2824 textIndex = tempIndex; | |
2825 replaceIndex = i; | |
2826 } | |
2827 } | |
2828 } | |
2829 // NOTE: logic duplicated above END | |
2830 | |
2831 } | |
2832 int textLength = text.length(); | |
2833 for (int i = start; i < textLength; i++) | |
2834 { | |
2835 buf.append(text.charAt(i)); | |
2836 } | |
2837 String result = buf.toString(); | |
2838 if (!repeat) | |
2839 { | |
2840 return result; | |
2841 } | |
2842 | |
2843 return replaceEach(result, searchList, replacementList, repeat, timeToLive -
1); | |
2844 } | |
2845 | |
2846 // Replace, character based | |
2847 //----------------------------------------------------------------------- | |
2848 | |
2849 /** | |
2850 * <p>Replaces all occurrences of a character in a String with another. | |
2851 * This is a null-safe version of {@link String#replace(char, char)}.</p> | |
2852 * <p/> | |
2853 * <p>A <code>null</code> string input returns <code>null</code>. | |
2854 * An empty ("") string input returns an empty string.</p> | |
2855 * <p/> | |
2856 * <pre> | |
2857 * StringUtils.replaceChars(null, *, *) = null | |
2858 * StringUtils.replaceChars("", *, *) = "" | |
2859 * StringUtils.replaceChars("abcba", 'b', 'y') = "aycya" | |
2860 * StringUtils.replaceChars("abcba", 'z', 'y') = "abcba" | |
2861 * </pre> | |
2862 * | |
2863 * @param str String to replace characters in, may be null | |
2864 * @param searchChar the character to search for, may be null | |
2865 * @param replaceChar the character to replace, may be null | |
2866 * @return modified String, <code>null</code> if null string input | |
2867 * @since 2.0 | |
2868 */ | |
2869 public static String replaceChars(String str, char searchChar, char replaceCha
r) | |
2870 { | |
2871 if (str == null) | |
2872 { | |
2873 return null; | |
2874 } | |
2875 return str.replace(searchChar, replaceChar); | |
2876 } | |
2877 | |
2878 /** | |
2879 * <p>Replaces multiple characters in a String in one go. | |
2880 * This method can also be used to delete characters.</p> | |
2881 * <p/> | |
2882 * <p>For example:<br /> | |
2883 * <code>replaceChars("hello", "ho", "jy") = jel
ly</code>.</p> | |
2884 * <p/> | |
2885 * <p>A <code>null</code> string input returns <code>null</code>. | |
2886 * An empty ("") string input returns an empty string. | |
2887 * A null or empty set of search characters returns the input string.</p> | |
2888 * <p/> | |
2889 * <p>The length of the search characters should normally equal the length | |
2890 * of the replace characters. | |
2891 * If the search characters is longer, then the extra search characters | |
2892 * are deleted. | |
2893 * If the search characters is shorter, then the extra replace characters | |
2894 * are ignored.</p> | |
2895 * <p/> | |
2896 * <pre> | |
2897 * StringUtils.replaceChars(null, *, *) = null | |
2898 * StringUtils.replaceChars("", *, *) = "" | |
2899 * StringUtils.replaceChars("abc", null, *) = "abc" | |
2900 * StringUtils.replaceChars("abc", "", *) = "abc" | |
2901 * StringUtils.replaceChars("abc", "b", null) = "ac" | |
2902 * StringUtils.replaceChars("abc", "b", "") = "ac" | |
2903 * StringUtils.replaceChars("abcba", "bc", "yz") = "ayzya" | |
2904 * StringUtils.replaceChars("abcba", "bc", "y") = "ayya" | |
2905 * StringUtils.replaceChars("abcba", "bc", "yzx") = "ayzya" | |
2906 * </pre> | |
2907 * | |
2908 * @param str String to replace characters in, may be null | |
2909 * @param searchChars a set of characters to search for, may be null | |
2910 * @param replaceChars a set of characters to replace, may be null | |
2911 * @return modified String, <code>null</code> if null string input | |
2912 * @since 2.0 | |
2913 */ | |
2914 public static String replaceChars(String str, String searchChars, String repla
ceChars) | |
2915 { | |
2916 if (isEmpty(str) || isEmpty(searchChars)) | |
2917 { | |
2918 return str; | |
2919 } | |
2920 if (replaceChars == null) | |
2921 { | |
2922 replaceChars = EMPTY; | |
2923 } | |
2924 boolean modified = false; | |
2925 int replaceCharsLength = replaceChars.length(); | |
2926 int strLength = str.length(); | |
2927 StringBuffer buf = new StringBuffer(strLength); | |
2928 for (int i = 0; i < strLength; i++) | |
2929 { | |
2930 char ch = str.charAt(i); | |
2931 int index = searchChars.indexOf(ch); | |
2932 if (index >= 0) | |
2933 { | |
2934 modified = true; | |
2935 if (index < replaceCharsLength) | |
2936 { | |
2937 buf.append(replaceChars.charAt(index)); | |
2938 } | |
2939 } else | |
2940 { | |
2941 buf.append(ch); | |
2942 } | |
2943 } | |
2944 if (modified) | |
2945 { | |
2946 return buf.toString(); | |
2947 } | |
2948 return str; | |
2949 } | |
2950 | |
2951 // Overlay | |
2952 //----------------------------------------------------------------------- | |
2953 | |
2954 /** | |
2955 * <p>Overlays part of a String with another String.</p> | |
2956 * <p/> | |
2957 * <pre> | |
2958 * StringUtils.overlayString(null, *, *, *) = NullPointerException | |
2959 * StringUtils.overlayString(*, null, *, *) = NullPointerException | |
2960 * StringUtils.overlayString("", "abc", 0, 0) = "abc" | |
2961 * StringUtils.overlayString("abcdef", null, 2, 4) = "abef" | |
2962 * StringUtils.overlayString("abcdef", "", 2, 4) = "abef" | |
2963 * StringUtils.overlayString("abcdef", "zzzz", 2, 4) = "abzzzzef" | |
2964 * StringUtils.overlayString("abcdef", "zzzz", 4, 2) = "abcdzzzzcdef" | |
2965 * StringUtils.overlayString("abcdef", "zzzz", -1, 4) = IndexOutOfBoundsExcept
ion | |
2966 * StringUtils.overlayString("abcdef", "zzzz", 2, 8) = IndexOutOfBoundsExcept
ion | |
2967 * </pre> | |
2968 * | |
2969 * @param text the String to do overlaying in, may be null | |
2970 * @param overlay the String to overlay, may be null | |
2971 * @param start the position to start overlaying at, must be valid | |
2972 * @param end the position to stop overlaying before, must be valid | |
2973 * @return overlayed String, <code>null</code> if null String input | |
2974 * @throws NullPointerException if text or overlay is null | |
2975 * @throws IndexOutOfBoundsException if either position is invalid | |
2976 * @deprecated Use better named {@link #overlay(String, String, int, int)} ins
tead. | |
2977 * Method will be removed in Commons Lang 3.0. | |
2978 */ | |
2979 public static String overlayString(String text, String overlay, int start, int
end) | |
2980 { | |
2981 return new StringBuffer(start + overlay.length() + text.length() - end + 1) | |
2982 .append(text.substring(0, start)) | |
2983 .append(overlay) | |
2984 .append(text.substring(end)) | |
2985 .toString(); | |
2986 } | |
2987 | |
2988 /** | |
2989 * <p>Overlays part of a String with another String.</p> | |
2990 * <p/> | |
2991 * <p>A <code>null</code> string input returns <code>null</code>. | |
2992 * A negative index is treated as zero. | |
2993 * An index greater than the string length is treated as the string length. | |
2994 * The start index is always the smaller of the two indices.</p> | |
2995 * <p/> | |
2996 * <pre> | |
2997 * StringUtils.overlay(null, *, *, *) = null | |
2998 * StringUtils.overlay("", "abc", 0, 0) = "abc" | |
2999 * StringUtils.overlay("abcdef", null, 2, 4) = "abef" | |
3000 * StringUtils.overlay("abcdef", "", 2, 4) = "abef" | |
3001 * StringUtils.overlay("abcdef", "", 4, 2) = "abef" | |
3002 * StringUtils.overlay("abcdef", "zzzz", 2, 4) = "abzzzzef" | |
3003 * StringUtils.overlay("abcdef", "zzzz", 4, 2) = "abzzzzef" | |
3004 * StringUtils.overlay("abcdef", "zzzz", -1, 4) = "zzzzef" | |
3005 * StringUtils.overlay("abcdef", "zzzz", 2, 8) = "abzzzz" | |
3006 * StringUtils.overlay("abcdef", "zzzz", -2, -3) = "zzzzabcdef" | |
3007 * StringUtils.overlay("abcdef", "zzzz", 8, 10) = "abcdefzzzz" | |
3008 * </pre> | |
3009 * | |
3010 * @param str the String to do overlaying in, may be null | |
3011 * @param overlay the String to overlay, may be null | |
3012 * @param start the position to start overlaying at | |
3013 * @param end the position to stop overlaying before | |
3014 * @return overlayed String, <code>null</code> if null String input | |
3015 * @since 2.0 | |
3016 */ | |
3017 public static String overlay(String str, String overlay, int start, int end) | |
3018 { | |
3019 if (str == null) | |
3020 { | |
3021 return null; | |
3022 } | |
3023 if (overlay == null) | |
3024 { | |
3025 overlay = EMPTY; | |
3026 } | |
3027 int len = str.length(); | |
3028 if (start < 0) | |
3029 { | |
3030 start = 0; | |
3031 } | |
3032 if (start > len) | |
3033 { | |
3034 start = len; | |
3035 } | |
3036 if (end < 0) | |
3037 { | |
3038 end = 0; | |
3039 } | |
3040 if (end > len) | |
3041 { | |
3042 end = len; | |
3043 } | |
3044 if (start > end) | |
3045 { | |
3046 int temp = start; | |
3047 start = end; | |
3048 end = temp; | |
3049 } | |
3050 return new StringBuffer(len + start - end + overlay.length() + 1) | |
3051 .append(str.substring(0, start)) | |
3052 .append(overlay) | |
3053 .append(str.substring(end)) | |
3054 .toString(); | |
3055 } | |
3056 | |
3057 // Chomping | |
3058 //----------------------------------------------------------------------- | |
3059 | |
3060 /** | |
3061 * <p>Removes one newline from end of a String if it's there, | |
3062 * otherwise leave it alone. A newline is "<code>\n</code>", | |
3063 * "<code>\r</code>", or "<code>\r\n</code>".</p> | |
3064 * <p/> | |
3065 * <p>NOTE: This method changed in 2.0. | |
3066 * It now more closely matches Perl chomp.</p> | |
3067 * <p/> | |
3068 * <pre> | |
3069 * StringUtils.chomp(null) = null | |
3070 * StringUtils.chomp("") = "" | |
3071 * StringUtils.chomp("abc \r") = "abc " | |
3072 * StringUtils.chomp("abc\n") = "abc" | |
3073 * StringUtils.chomp("abc\r\n") = "abc" | |
3074 * StringUtils.chomp("abc\r\n\r\n") = "abc\r\n" | |
3075 * StringUtils.chomp("abc\n\r") = "abc\n" | |
3076 * StringUtils.chomp("abc\n\rabc") = "abc\n\rabc" | |
3077 * StringUtils.chomp("\r") = "" | |
3078 * StringUtils.chomp("\n") = "" | |
3079 * StringUtils.chomp("\r\n") = "" | |
3080 * </pre> | |
3081 * | |
3082 * @param str the String to chomp a newline from, may be null | |
3083 * @return String without newline, <code>null</code> if null String input | |
3084 */ | |
3085 public static String chomp(String str) | |
3086 { | |
3087 if (isEmpty(str)) | |
3088 { | |
3089 return str; | |
3090 } | |
3091 | |
3092 if (str.length() == 1) | |
3093 { | |
3094 char ch = str.charAt(0); | |
3095 if (ch == CharUtils.CR || ch == CharUtils.LF) | |
3096 { | |
3097 return EMPTY; | |
3098 } | |
3099 return str; | |
3100 } | |
3101 | |
3102 int lastIdx = str.length() - 1; | |
3103 char last = str.charAt(lastIdx); | |
3104 | |
3105 if (last == CharUtils.LF) | |
3106 { | |
3107 if (str.charAt(lastIdx - 1) == CharUtils.CR) | |
3108 { | |
3109 lastIdx--; | |
3110 } | |
3111 } else if (last != CharUtils.CR) | |
3112 { | |
3113 lastIdx++; | |
3114 } | |
3115 return str.substring(0, lastIdx); | |
3116 } | |
3117 | |
3118 /** | |
3119 * <p>Removes <code>separator</code> from the end of | |
3120 * <code>str</code> if it's there, otherwise leave it alone.</p> | |
3121 * <p/> | |
3122 * <p>NOTE: This method changed in version 2.0. | |
3123 * It now more closely matches Perl chomp. | |
3124 * For the previous behavior, use {@link #substringBeforeLast(String, String)}
. | |
3125 * This method uses {@link String#endsWith(String)}.</p> | |
3126 * <p/> | |
3127 * <pre> | |
3128 * StringUtils.chomp(null, *) = null | |
3129 * StringUtils.chomp("", *) = "" | |
3130 * StringUtils.chomp("foobar", "bar") = "foo" | |
3131 * StringUtils.chomp("foobar", "baz") = "foobar" | |
3132 * StringUtils.chomp("foo", "foo") = "" | |
3133 * StringUtils.chomp("foo ", "foo") = "foo " | |
3134 * StringUtils.chomp(" foo", "foo") = " " | |
3135 * StringUtils.chomp("foo", "foooo") = "foo" | |
3136 * StringUtils.chomp("foo", "") = "foo" | |
3137 * StringUtils.chomp("foo", null) = "foo" | |
3138 * </pre> | |
3139 * | |
3140 * @param str the String to chomp from, may be null | |
3141 * @param separator separator String, may be null | |
3142 * @return String without trailing separator, <code>null</code> if null String
input | |
3143 */ | |
3144 public static String chomp(String str, String separator) | |
3145 { | |
3146 if (isEmpty(str) || separator == null) | |
3147 { | |
3148 return str; | |
3149 } | |
3150 if (str.endsWith(separator)) | |
3151 { | |
3152 return str.substring(0, str.length() - separator.length()); | |
3153 } | |
3154 return str; | |
3155 } | |
3156 | |
3157 /** | |
3158 * <p>Remove any "\n" if and only if it is at the end | |
3159 * of the supplied String.</p> | |
3160 * | |
3161 * @param str the String to chomp from, must not be null | |
3162 * @return String without chomped ending | |
3163 * @throws NullPointerException if str is <code>null</code> | |
3164 * @deprecated Use {@link #chomp(String)} instead. | |
3165 * Method will be removed in Commons Lang 3.0. | |
3166 */ | |
3167 public static String chompLast(String str) | |
3168 { | |
3169 return chompLast(str, "\n"); | |
3170 } | |
3171 | |
3172 /** | |
3173 * <p>Remove a value if and only if the String ends with that value.</p> | |
3174 * | |
3175 * @param str the String to chomp from, must not be null | |
3176 * @param sep the String to chomp, must not be null | |
3177 * @return String without chomped ending | |
3178 * @throws NullPointerException if str or sep is <code>null</code> | |
3179 * @deprecated Use {@link #chomp(String, String)} instead. | |
3180 * Method will be removed in Commons Lang 3.0. | |
3181 */ | |
3182 public static String chompLast(String str, String sep) | |
3183 { | |
3184 if (str.length() == 0) | |
3185 { | |
3186 return str; | |
3187 } | |
3188 String sub = str.substring(str.length() - sep.length()); | |
3189 if (sep.equals(sub)) | |
3190 { | |
3191 return str.substring(0, str.length() - sep.length()); | |
3192 } | |
3193 return str; | |
3194 } | |
3195 | |
3196 /** | |
3197 * <p>Remove everything and return the last value of a supplied String, and | |
3198 * everything after it from a String.</p> | |
3199 * | |
3200 * @param str the String to chomp from, must not be null | |
3201 * @param sep the String to chomp, must not be null | |
3202 * @return String chomped | |
3203 * @throws NullPointerException if str or sep is <code>null</code> | |
3204 * @deprecated Use {@link #substringAfterLast(String, String)} instead | |
3205 * (although this doesn't include the separator) | |
3206 * Method will be removed in Commons Lang 3.0. | |
3207 */ | |
3208 public static String getChomp(String str, String sep) | |
3209 { | |
3210 int idx = str.lastIndexOf(sep); | |
3211 if (idx == str.length() - sep.length()) | |
3212 { | |
3213 return sep; | |
3214 } else if (idx != -1) | |
3215 { | |
3216 return str.substring(idx); | |
3217 } else | |
3218 { | |
3219 return EMPTY; | |
3220 } | |
3221 } | |
3222 | |
3223 /** | |
3224 * <p>Remove the first value of a supplied String, and everything before it | |
3225 * from a String.</p> | |
3226 * | |
3227 * @param str the String to chomp from, must not be null | |
3228 * @param sep the String to chomp, must not be null | |
3229 * @return String without chomped beginning | |
3230 * @throws NullPointerException if str or sep is <code>null</code> | |
3231 * @deprecated Use {@link #substringAfter(String, String)} instead. | |
3232 * Method will be removed in Commons Lang 3.0. | |
3233 */ | |
3234 public static String prechomp(String str, String sep) | |
3235 { | |
3236 int idx = str.indexOf(sep); | |
3237 if (idx == -1) | |
3238 { | |
3239 return str; | |
3240 } | |
3241 return str.substring(idx + sep.length()); | |
3242 } | |
3243 | |
3244 /** | |
3245 * <p>Remove and return everything before the first value of a | |
3246 * supplied String from another String.</p> | |
3247 * | |
3248 * @param str the String to chomp from, must not be null | |
3249 * @param sep the String to chomp, must not be null | |
3250 * @return String prechomped | |
3251 * @throws NullPointerException if str or sep is <code>null</code> | |
3252 * @deprecated Use {@link #substringBefore(String, String)} instead | |
3253 * (although this doesn't include the separator). | |
3254 * Method will be removed in Commons Lang 3.0. | |
3255 */ | |
3256 public static String getPrechomp(String str, String sep) | |
3257 { | |
3258 int idx = str.indexOf(sep); | |
3259 if (idx == -1) | |
3260 { | |
3261 return EMPTY; | |
3262 } | |
3263 return str.substring(0, idx + sep.length()); | |
3264 } | |
3265 | |
3266 // Chopping | |
3267 //----------------------------------------------------------------------- | |
3268 | |
3269 /** | |
3270 * <p>Remove the last character from a String.</p> | |
3271 * <p/> | |
3272 * <p>If the String ends in <code>\r\n</code>, then remove both | |
3273 * of them.</p> | |
3274 * <p/> | |
3275 * <pre> | |
3276 * StringUtils.chop(null) = null | |
3277 * StringUtils.chop("") = "" | |
3278 * StringUtils.chop("abc \r") = "abc " | |
3279 * StringUtils.chop("abc\n") = "abc" | |
3280 * StringUtils.chop("abc\r\n") = "abc" | |
3281 * StringUtils.chop("abc") = "ab" | |
3282 * StringUtils.chop("abc\nabc") = "abc\nab" | |
3283 * StringUtils.chop("a") = "" | |
3284 * StringUtils.chop("\r") = "" | |
3285 * StringUtils.chop("\n") = "" | |
3286 * StringUtils.chop("\r\n") = "" | |
3287 * </pre> | |
3288 * | |
3289 * @param str the String to chop last character from, may be null | |
3290 * @return String without last character, <code>null</code> if null String inp
ut | |
3291 */ | |
3292 public static String chop(String str) | |
3293 { | |
3294 if (str == null) | |
3295 { | |
3296 return null; | |
3297 } | |
3298 int strLen = str.length(); | |
3299 if (strLen < 2) | |
3300 { | |
3301 return EMPTY; | |
3302 } | |
3303 int lastIdx = strLen - 1; | |
3304 String ret = str.substring(0, lastIdx); | |
3305 char last = str.charAt(lastIdx); | |
3306 if (last == CharUtils.LF) | |
3307 { | |
3308 if (ret.charAt(lastIdx - 1) == CharUtils.CR) | |
3309 { | |
3310 return ret.substring(0, lastIdx - 1); | |
3311 } | |
3312 } | |
3313 return ret; | |
3314 } | |
3315 | |
3316 /** | |
3317 * <p>Removes <code>\n</code> from end of a String if it's there. | |
3318 * If a <code>\r</code> precedes it, then remove that too.</p> | |
3319 * | |
3320 * @param str the String to chop a newline from, must not be null | |
3321 * @return String without newline | |
3322 * @throws NullPointerException if str is <code>null</code> | |
3323 * @deprecated Use {@link #chomp(String)} instead. | |
3324 * Method will be removed in Commons Lang 3.0. | |
3325 */ | |
3326 public static String chopNewline(String str) | |
3327 { | |
3328 int lastIdx = str.length() - 1; | |
3329 if (lastIdx <= 0) | |
3330 { | |
3331 return EMPTY; | |
3332 } | |
3333 char last = str.charAt(lastIdx); | |
3334 if (last == CharUtils.LF) | |
3335 { | |
3336 if (str.charAt(lastIdx - 1) == CharUtils.CR) | |
3337 { | |
3338 lastIdx--; | |
3339 } | |
3340 } else | |
3341 { | |
3342 lastIdx++; | |
3343 } | |
3344 return str.substring(0, lastIdx); | |
3345 } | |
3346 | |
3347 // Conversion | |
3348 //----------------------------------------------------------------------- | |
3349 | |
3350 /** | |
3351 * <p>Escapes any values it finds into their String form.</p> | |
3352 * <p/> | |
3353 * <p>So a tab becomes the characters <code>'\\'</code> and | |
3354 * <code>'t'</code>.</p> | |
3355 * <p/> | |
3356 * <p>As of Lang 2.0, this calls {@link StringEscapeUtils#escapeJava(String)} | |
3357 * behind the scenes. | |
3358 * </p> | |
3359 * | |
3360 * @param str String to escape values in | |
3361 * @return String with escaped values | |
3362 * @throws NullPointerException if str is <code>null</code> | |
3363 * @see StringEscapeUtils#escapeJava(java.lang.String) | |
3364 * @deprecated Use {@link StringEscapeUtils#escapeJava(String)} | |
3365 * This method will be removed in Commons Lang 3.0 | |
3366 */ | |
3367 public static String escape(String str) | |
3368 { | |
3369 return StringEscapeUtils.escapeJava(str); | |
3370 } | |
3371 | |
3372 // Padding | |
3373 //----------------------------------------------------------------------- | |
3374 | |
3375 /** | |
3376 * <p>Repeat a String <code>repeat</code> times to form a | |
3377 * new String.</p> | |
3378 * <p/> | |
3379 * <pre> | |
3380 * StringUtils.repeat(null, 2) = null | |
3381 * StringUtils.repeat("", 0) = "" | |
3382 * StringUtils.repeat("", 2) = "" | |
3383 * StringUtils.repeat("a", 3) = "aaa" | |
3384 * StringUtils.repeat("ab", 2) = "abab" | |
3385 * StringUtils.repeat("a", -2) = "" | |
3386 * </pre> | |
3387 * | |
3388 * @param str the String to repeat, may be null | |
3389 * @param repeat number of times to repeat str, negative treated as zero | |
3390 * @return a new String consisting of the original String repeated, | |
3391 * <code>null</code> if null String input | |
3392 */ | |
3393 public static String repeat(String str, int repeat) | |
3394 { | |
3395 // Performance tuned for 2.0 (JDK1.4) | |
3396 | |
3397 if (str == null) | |
3398 { | |
3399 return null; | |
3400 } | |
3401 if (repeat <= 0) | |
3402 { | |
3403 return EMPTY; | |
3404 } | |
3405 int inputLength = str.length(); | |
3406 if (repeat == 1 || inputLength == 0) | |
3407 { | |
3408 return str; | |
3409 } | |
3410 if (inputLength == 1 && repeat <= PAD_LIMIT) | |
3411 { | |
3412 return padding(repeat, str.charAt(0)); | |
3413 } | |
3414 | |
3415 int outputLength = inputLength * repeat; | |
3416 switch (inputLength) | |
3417 { | |
3418 case 1: | |
3419 char ch = str.charAt(0); | |
3420 char[] output1 = new char[outputLength]; | |
3421 for (int i = repeat - 1; i >= 0; i--) | |
3422 { | |
3423 output1[i] = ch; | |
3424 } | |
3425 return new String(output1); | |
3426 case 2: | |
3427 char ch0 = str.charAt(0); | |
3428 char ch1 = str.charAt(1); | |
3429 char[] output2 = new char[outputLength]; | |
3430 for (int i = repeat * 2 - 2; i >= 0; i--, i--) | |
3431 { | |
3432 output2[i] = ch0; | |
3433 output2[i + 1] = ch1; | |
3434 } | |
3435 return new String(output2); | |
3436 default: | |
3437 StringBuffer buf = new StringBuffer(outputLength); | |
3438 for (int i = 0; i < repeat; i++) | |
3439 { | |
3440 buf.append(str); | |
3441 } | |
3442 return buf.toString(); | |
3443 } | |
3444 } | |
3445 | |
3446 /** | |
3447 * <p>Returns padding using the specified delimiter repeated | |
3448 * to a given length.</p> | |
3449 * <p/> | |
3450 * <pre> | |
3451 * StringUtils.padding(0, 'e') = "" | |
3452 * StringUtils.padding(3, 'e') = "eee" | |
3453 * StringUtils.padding(-2, 'e') = IndexOutOfBoundsException | |
3454 * </pre> | |
3455 * <p/> | |
3456 * <p>Note: this method doesn't not support padding with | |
3457 * <a href="http://www.unicode.org/glossary/#supplementary_character">Unicode
Supplementary Characters</a> | |
3458 * as they require a pair of <code>char</code>s to be represented. | |
3459 * If you are needing to support full I18N of your applications | |
3460 * consider using {@link #repeat(String, int)} instead. | |
3461 * </p> | |
3462 * | |
3463 * @param repeat number of times to repeat delim | |
3464 * @param padChar character to repeat | |
3465 * @return String with repeated character | |
3466 * @throws IndexOutOfBoundsException if <code>repeat < 0</code> | |
3467 * @see #repeat(String, int) | |
3468 */ | |
3469 private static String padding(int repeat, char padChar) throws IndexOutOfBound
sException | |
3470 { | |
3471 if (repeat < 0) | |
3472 { | |
3473 throw new IndexOutOfBoundsException("Cannot pad a negative amount: " + rep
eat); | |
3474 } | |
3475 final char[] buf = new char[repeat]; | |
3476 for (int i = 0; i < buf.length; i++) | |
3477 { | |
3478 buf[i] = padChar; | |
3479 } | |
3480 return new String(buf); | |
3481 } | |
3482 | |
3483 /** | |
3484 * <p>Right pad a String with spaces (' ').</p> | |
3485 * <p/> | |
3486 * <p>The String is padded to the size of <code>size</code>.</p> | |
3487 * <p/> | |
3488 * <pre> | |
3489 * StringUtils.rightPad(null, *) = null | |
3490 * StringUtils.rightPad("", 3) = " " | |
3491 * StringUtils.rightPad("bat", 3) = "bat" | |
3492 * StringUtils.rightPad("bat", 5) = "bat " | |
3493 * StringUtils.rightPad("bat", 1) = "bat" | |
3494 * StringUtils.rightPad("bat", -1) = "bat" | |
3495 * </pre> | |
3496 * | |
3497 * @param str the String to pad out, may be null | |
3498 * @param size the size to pad to | |
3499 * @return right padded String or original String if no padding is necessary, | |
3500 * <code>null</code> if null String input | |
3501 */ | |
3502 public static String rightPad(String str, int size) | |
3503 { | |
3504 return rightPad(str, size, ' '); | |
3505 } | |
3506 | |
3507 /** | |
3508 * <p>Right pad a String with a specified character.</p> | |
3509 * <p/> | |
3510 * <p>The String is padded to the size of <code>size</code>.</p> | |
3511 * <p/> | |
3512 * <pre> | |
3513 * StringUtils.rightPad(null, *, *) = null | |
3514 * StringUtils.rightPad("", 3, 'z') = "zzz" | |
3515 * StringUtils.rightPad("bat", 3, 'z') = "bat" | |
3516 * StringUtils.rightPad("bat", 5, 'z') = "batzz" | |
3517 * StringUtils.rightPad("bat", 1, 'z') = "bat" | |
3518 * StringUtils.rightPad("bat", -1, 'z') = "bat" | |
3519 * </pre> | |
3520 * | |
3521 * @param str the String to pad out, may be null | |
3522 * @param size the size to pad to | |
3523 * @param padChar the character to pad with | |
3524 * @return right padded String or original String if no padding is necessary, | |
3525 * <code>null</code> if null String input | |
3526 * @since 2.0 | |
3527 */ | |
3528 public static String rightPad(String str, int size, char padChar) | |
3529 { | |
3530 if (str == null) | |
3531 { | |
3532 return null; | |
3533 } | |
3534 int pads = size - str.length(); | |
3535 if (pads <= 0) | |
3536 { | |
3537 return str; // returns original String when possible | |
3538 } | |
3539 if (pads > PAD_LIMIT) | |
3540 { | |
3541 return rightPad(str, size, String.valueOf(padChar)); | |
3542 } | |
3543 return str.concat(padding(pads, padChar)); | |
3544 } | |
3545 | |
3546 /** | |
3547 * <p>Right pad a String with a specified String.</p> | |
3548 * <p/> | |
3549 * <p>The String is padded to the size of <code>size</code>.</p> | |
3550 * <p/> | |
3551 * <pre> | |
3552 * StringUtils.rightPad(null, *, *) = null | |
3553 * StringUtils.rightPad("", 3, "z") = "zzz" | |
3554 * StringUtils.rightPad("bat", 3, "yz") = "bat" | |
3555 * StringUtils.rightPad("bat", 5, "yz") = "batyz" | |
3556 * StringUtils.rightPad("bat", 8, "yz") = "batyzyzy" | |
3557 * StringUtils.rightPad("bat", 1, "yz") = "bat" | |
3558 * StringUtils.rightPad("bat", -1, "yz") = "bat" | |
3559 * StringUtils.rightPad("bat", 5, null) = "bat " | |
3560 * StringUtils.rightPad("bat", 5, "") = "bat " | |
3561 * </pre> | |
3562 * | |
3563 * @param str the String to pad out, may be null | |
3564 * @param size the size to pad to | |
3565 * @param padStr the String to pad with, null or empty treated as single space | |
3566 * @return right padded String or original String if no padding is necessary, | |
3567 * <code>null</code> if null String input | |
3568 */ | |
3569 public static String rightPad(String str, int size, String padStr) | |
3570 { | |
3571 if (str == null) | |
3572 { | |
3573 return null; | |
3574 } | |
3575 if (isEmpty(padStr)) | |
3576 { | |
3577 padStr = " "; | |
3578 } | |
3579 int padLen = padStr.length(); | |
3580 int strLen = str.length(); | |
3581 int pads = size - strLen; | |
3582 if (pads <= 0) | |
3583 { | |
3584 return str; // returns original String when possible | |
3585 } | |
3586 if (padLen == 1 && pads <= PAD_LIMIT) | |
3587 { | |
3588 return rightPad(str, size, padStr.charAt(0)); | |
3589 } | |
3590 | |
3591 if (pads == padLen) | |
3592 { | |
3593 return str.concat(padStr); | |
3594 } else if (pads < padLen) | |
3595 { | |
3596 return str.concat(padStr.substring(0, pads)); | |
3597 } else | |
3598 { | |
3599 char[] padding = new char[pads]; | |
3600 char[] padChars = padStr.toCharArray(); | |
3601 for (int i = 0; i < pads; i++) | |
3602 { | |
3603 padding[i] = padChars[i % padLen]; | |
3604 } | |
3605 return str.concat(new String(padding)); | |
3606 } | |
3607 } | |
3608 | |
3609 /** | |
3610 * <p>Left pad a String with spaces (' ').</p> | |
3611 * <p/> | |
3612 * <p>The String is padded to the size of <code>size<code>.</p> | |
3613 * <p/> | |
3614 * <pre> | |
3615 * StringUtils.leftPad(null, *) = null | |
3616 * StringUtils.leftPad("", 3) = " " | |
3617 * StringUtils.leftPad("bat", 3) = "bat" | |
3618 * StringUtils.leftPad("bat", 5) = " bat" | |
3619 * StringUtils.leftPad("bat", 1) = "bat" | |
3620 * StringUtils.leftPad("bat", -1) = "bat" | |
3621 * </pre> | |
3622 * | |
3623 * @param str the String to pad out, may be null | |
3624 * @param size the size to pad to | |
3625 * @return left padded String or original String if no padding is necessary, | |
3626 * <code>null</code> if null String input | |
3627 */ | |
3628 public static String leftPad(String str, int size) | |
3629 { | |
3630 return leftPad(str, size, ' '); | |
3631 } | |
3632 | |
3633 /** | |
3634 * <p>Left pad a String with a specified character.</p> | |
3635 * <p/> | |
3636 * <p>Pad to a size of <code>size</code>.</p> | |
3637 * <p/> | |
3638 * <pre> | |
3639 * StringUtils.leftPad(null, *, *) = null | |
3640 * StringUtils.leftPad("", 3, 'z') = "zzz" | |
3641 * StringUtils.leftPad("bat", 3, 'z') = "bat" | |
3642 * StringUtils.leftPad("bat", 5, 'z') = "zzbat" | |
3643 * StringUtils.leftPad("bat", 1, 'z') = "bat" | |
3644 * StringUtils.leftPad("bat", -1, 'z') = "bat" | |
3645 * </pre> | |
3646 * | |
3647 * @param str the String to pad out, may be null | |
3648 * @param size the size to pad to | |
3649 * @param padChar the character to pad with | |
3650 * @return left padded String or original String if no padding is necessary, | |
3651 * <code>null</code> if null String input | |
3652 * @since 2.0 | |
3653 */ | |
3654 public static String leftPad(String str, int size, char padChar) | |
3655 { | |
3656 if (str == null) | |
3657 { | |
3658 return null; | |
3659 } | |
3660 int pads = size - str.length(); | |
3661 if (pads <= 0) | |
3662 { | |
3663 return str; // returns original String when possible | |
3664 } | |
3665 if (pads > PAD_LIMIT) | |
3666 { | |
3667 return leftPad(str, size, String.valueOf(padChar)); | |
3668 } | |
3669 return padding(pads, padChar).concat(str); | |
3670 } | |
3671 | |
3672 /** | |
3673 * <p>Left pad a String with a specified String.</p> | |
3674 * <p/> | |
3675 * <p>Pad to a size of <code>size</code>.</p> | |
3676 * <p/> | |
3677 * <pre> | |
3678 * StringUtils.leftPad(null, *, *) = null | |
3679 * StringUtils.leftPad("", 3, "z") = "zzz" | |
3680 * StringUtils.leftPad("bat", 3, "yz") = "bat" | |
3681 * StringUtils.leftPad("bat", 5, "yz") = "yzbat" | |
3682 * StringUtils.leftPad("bat", 8, "yz") = "yzyzybat" | |
3683 * StringUtils.leftPad("bat", 1, "yz") = "bat" | |
3684 * StringUtils.leftPad("bat", -1, "yz") = "bat" | |
3685 * StringUtils.leftPad("bat", 5, null) = " bat" | |
3686 * StringUtils.leftPad("bat", 5, "") = " bat" | |
3687 * </pre> | |
3688 * | |
3689 * @param str the String to pad out, may be null | |
3690 * @param size the size to pad to | |
3691 * @param padStr the String to pad with, null or empty treated as single space | |
3692 * @return left padded String or original String if no padding is necessary, | |
3693 * <code>null</code> if null String input | |
3694 */ | |
3695 public static String leftPad(String str, int size, String padStr) | |
3696 { | |
3697 if (str == null) | |
3698 { | |
3699 return null; | |
3700 } | |
3701 if (isEmpty(padStr)) | |
3702 { | |
3703 padStr = " "; | |
3704 } | |
3705 int padLen = padStr.length(); | |
3706 int strLen = str.length(); | |
3707 int pads = size - strLen; | |
3708 if (pads <= 0) | |
3709 { | |
3710 return str; // returns original String when possible | |
3711 } | |
3712 if (padLen == 1 && pads <= PAD_LIMIT) | |
3713 { | |
3714 return leftPad(str, size, padStr.charAt(0)); | |
3715 } | |
3716 | |
3717 if (pads == padLen) | |
3718 { | |
3719 return padStr.concat(str); | |
3720 } else if (pads < padLen) | |
3721 { | |
3722 return padStr.substring(0, pads).concat(str); | |
3723 } else | |
3724 { | |
3725 char[] padding = new char[pads]; | |
3726 char[] padChars = padStr.toCharArray(); | |
3727 for (int i = 0; i < pads; i++) | |
3728 { | |
3729 padding[i] = padChars[i % padLen]; | |
3730 } | |
3731 return new String(padding).concat(str); | |
3732 } | |
3733 } | |
3734 | |
3735 /** | |
3736 * Gets a String's length or <code>0</code> if the String is <code>null</code>
. | |
3737 * | |
3738 * @param str a String or <code>null</code> | |
3739 * @return String length or <code>0</code> if the String is <code>null</code>. | |
3740 * @since 2.4 | |
3741 */ | |
3742 public static int length(String str) | |
3743 { | |
3744 return str == null ? 0 : str.length(); | |
3745 } | |
3746 | |
3747 // Centering | |
3748 //----------------------------------------------------------------------- | |
3749 | |
3750 /** | |
3751 * <p>Centers a String in a larger String of size <code>size</code> | |
3752 * using the space character (' ').<p> | |
3753 * <p/> | |
3754 * <p>If the size is less than the String length, the String is returned. | |
3755 * A <code>null</code> String returns <code>null</code>. | |
3756 * A negative size is treated as zero.</p> | |
3757 * <p/> | |
3758 * <p>Equivalent to <code>center(str, size, " ")</code>.</p> | |
3759 * <p/> | |
3760 * <pre> | |
3761 * StringUtils.center(null, *) = null | |
3762 * StringUtils.center("", 4) = " " | |
3763 * StringUtils.center("ab", -1) = "ab" | |
3764 * StringUtils.center("ab", 4) = " ab " | |
3765 * StringUtils.center("abcd", 2) = "abcd" | |
3766 * StringUtils.center("a", 4) = " a " | |
3767 * </pre> | |
3768 * | |
3769 * @param str the String to center, may be null | |
3770 * @param size the int size of new String, negative treated as zero | |
3771 * @return centered String, <code>null</code> if null String input | |
3772 */ | |
3773 public static String center(String str, int size) | |
3774 { | |
3775 return center(str, size, ' '); | |
3776 } | |
3777 | |
3778 /** | |
3779 * <p>Centers a String in a larger String of size <code>size</code>. | |
3780 * Uses a supplied character as the value to pad the String with.</p> | |
3781 * <p/> | |
3782 * <p>If the size is less than the String length, the String is returned. | |
3783 * A <code>null</code> String returns <code>null</code>. | |
3784 * A negative size is treated as zero.</p> | |
3785 * <p/> | |
3786 * <pre> | |
3787 * StringUtils.center(null, *, *) = null | |
3788 * StringUtils.center("", 4, ' ') = " " | |
3789 * StringUtils.center("ab", -1, ' ') = "ab" | |
3790 * StringUtils.center("ab", 4, ' ') = " ab" | |
3791 * StringUtils.center("abcd", 2, ' ') = "abcd" | |
3792 * StringUtils.center("a", 4, ' ') = " a " | |
3793 * StringUtils.center("a", 4, 'y') = "yayy" | |
3794 * </pre> | |
3795 * | |
3796 * @param str the String to center, may be null | |
3797 * @param size the int size of new String, negative treated as zero | |
3798 * @param padChar the character to pad the new String with | |
3799 * @return centered String, <code>null</code> if null String input | |
3800 * @since 2.0 | |
3801 */ | |
3802 public static String center(String str, int size, char padChar) | |
3803 { | |
3804 if (str == null || size <= 0) | |
3805 { | |
3806 return str; | |
3807 } | |
3808 int strLen = str.length(); | |
3809 int pads = size - strLen; | |
3810 if (pads <= 0) | |
3811 { | |
3812 return str; | |
3813 } | |
3814 str = leftPad(str, strLen + pads / 2, padChar); | |
3815 str = rightPad(str, size, padChar); | |
3816 return str; | |
3817 } | |
3818 | |
3819 /** | |
3820 * <p>Centers a String in a larger String of size <code>size</code>. | |
3821 * Uses a supplied String as the value to pad the String with.</p> | |
3822 * <p/> | |
3823 * <p>If the size is less than the String length, the String is returned. | |
3824 * A <code>null</code> String returns <code>null</code>. | |
3825 * A negative size is treated as zero.</p> | |
3826 * <p/> | |
3827 * <pre> | |
3828 * StringUtils.center(null, *, *) = null | |
3829 * StringUtils.center("", 4, " ") = " " | |
3830 * StringUtils.center("ab", -1, " ") = "ab" | |
3831 * StringUtils.center("ab", 4, " ") = " ab" | |
3832 * StringUtils.center("abcd", 2, " ") = "abcd" | |
3833 * StringUtils.center("a", 4, " ") = " a " | |
3834 * StringUtils.center("a", 4, "yz") = "yayz" | |
3835 * StringUtils.center("abc", 7, null) = " abc " | |
3836 * StringUtils.center("abc", 7, "") = " abc " | |
3837 * </pre> | |
3838 * | |
3839 * @param str the String to center, may be null | |
3840 * @param size the int size of new String, negative treated as zero | |
3841 * @param padStr the String to pad the new String with, must not be null or em
pty | |
3842 * @return centered String, <code>null</code> if null String input | |
3843 * @throws IllegalArgumentException if padStr is <code>null</code> or empty | |
3844 */ | |
3845 public static String center(String str, int size, String padStr) | |
3846 { | |
3847 if (str == null || size <= 0) | |
3848 { | |
3849 return str; | |
3850 } | |
3851 if (isEmpty(padStr)) | |
3852 { | |
3853 padStr = " "; | |
3854 } | |
3855 int strLen = str.length(); | |
3856 int pads = size - strLen; | |
3857 if (pads <= 0) | |
3858 { | |
3859 return str; | |
3860 } | |
3861 str = leftPad(str, strLen + pads / 2, padStr); | |
3862 str = rightPad(str, size, padStr); | |
3863 return str; | |
3864 } | |
3865 | |
3866 // Case conversion | |
3867 //----------------------------------------------------------------------- | |
3868 | |
3869 /** | |
3870 * <p>Converts a String to upper case as per {@link String#toUpperCase()}.</p> | |
3871 * <p/> | |
3872 * <p>A <code>null</code> input String returns <code>null</code>.</p> | |
3873 * <p/> | |
3874 * <pre> | |
3875 * StringUtils.upperCase(null) = null | |
3876 * StringUtils.upperCase("") = "" | |
3877 * StringUtils.upperCase("aBc") = "ABC" | |
3878 * </pre> | |
3879 * | |
3880 * @param str the String to upper case, may be null | |
3881 * @return the upper cased String, <code>null</code> if null String input | |
3882 */ | |
3883 public static String upperCase(String str) | |
3884 { | |
3885 if (str == null) | |
3886 { | |
3887 return null; | |
3888 } | |
3889 return str.toUpperCase(); | |
3890 } | |
3891 | |
3892 /** | |
3893 * <p>Converts a String to lower case as per {@link String#toLowerCase()}.</p> | |
3894 * <p/> | |
3895 * <p>A <code>null</code> input String returns <code>null</code>.</p> | |
3896 * <p/> | |
3897 * <pre> | |
3898 * StringUtils.lowerCase(null) = null | |
3899 * StringUtils.lowerCase("") = "" | |
3900 * StringUtils.lowerCase("aBc") = "abc" | |
3901 * </pre> | |
3902 * | |
3903 * @param str the String to lower case, may be null | |
3904 * @return the lower cased String, <code>null</code> if null String input | |
3905 */ | |
3906 public static String lowerCase(String str) | |
3907 { | |
3908 if (str == null) | |
3909 { | |
3910 return null; | |
3911 } | |
3912 return str.toLowerCase(); | |
3913 } | |
3914 | |
3915 /** | |
3916 * <p>Capitalizes a String changing the first letter to title case as | |
3917 * per {@link Character#toTitleCase(char)}. No other letters are changed.</p> | |
3918 * <p/> | |
3919 * <p>For a word based algorithm, see {@link WordUtils#capitalize(String)}. | |
3920 * A <code>null</code> input String returns <code>null</code>.</p> | |
3921 * <p/> | |
3922 * <pre> | |
3923 * StringUtils.capitalize(null) = null | |
3924 * StringUtils.capitalize("") = "" | |
3925 * StringUtils.capitalize("cat") = "Cat" | |
3926 * StringUtils.capitalize("cAt") = "CAt" | |
3927 * </pre> | |
3928 * | |
3929 * @param str the String to capitalize, may be null | |
3930 * @return the capitalized String, <code>null</code> if null String input | |
3931 * @see WordUtils#capitalize(String) | |
3932 * @see #uncapitalize(String) | |
3933 * @since 2.0 | |
3934 */ | |
3935 public static String capitalize(String str) | |
3936 { | |
3937 int strLen; | |
3938 if (str == null || (strLen = str.length()) == 0) | |
3939 { | |
3940 return str; | |
3941 } | |
3942 return new StringBuffer(strLen) | |
3943 .append(Character.toTitleCase(str.charAt(0))) | |
3944 .append(str.substring(1)) | |
3945 .toString(); | |
3946 } | |
3947 | |
3948 /** | |
3949 * <p>Capitalizes a String changing the first letter to title case as | |
3950 * per {@link Character#toTitleCase(char)}. No other letters are changed.</p> | |
3951 * | |
3952 * @param str the String to capitalize, may be null | |
3953 * @return the capitalized String, <code>null</code> if null String input | |
3954 * @deprecated Use the standardly named {@link #capitalize(String)}. | |
3955 * Method will be removed in Commons Lang 3.0. | |
3956 */ | |
3957 public static String capitalise(String str) | |
3958 { | |
3959 return capitalize(str); | |
3960 } | |
3961 | |
3962 /** | |
3963 * <p>Uncapitalizes a String changing the first letter to title case as | |
3964 * per {@link Character#toLowerCase(char)}. No other letters are changed.</p> | |
3965 * <p/> | |
3966 * <p>For a word based algorithm, see {@link WordUtils#uncapitalize(String)}. | |
3967 * A <code>null</code> input String returns <code>null</code>.</p> | |
3968 * <p/> | |
3969 * <pre> | |
3970 * StringUtils.uncapitalize(null) = null | |
3971 * StringUtils.uncapitalize("") = "" | |
3972 * StringUtils.uncapitalize("Cat") = "cat" | |
3973 * StringUtils.uncapitalize("CAT") = "cAT" | |
3974 * </pre> | |
3975 * | |
3976 * @param str the String to uncapitalize, may be null | |
3977 * @return the uncapitalized String, <code>null</code> if null String input | |
3978 * @see WordUtils#uncapitalize(String) | |
3979 * @see #capitalize(String) | |
3980 * @since 2.0 | |
3981 */ | |
3982 public static String uncapitalize(String str) | |
3983 { | |
3984 int strLen; | |
3985 if (str == null || (strLen = str.length()) == 0) | |
3986 { | |
3987 return str; | |
3988 } | |
3989 return new StringBuffer(strLen) | |
3990 .append(Character.toLowerCase(str.charAt(0))) | |
3991 .append(str.substring(1)) | |
3992 .toString(); | |
3993 } | |
3994 | |
3995 /** | |
3996 * <p>Uncapitalizes a String changing the first letter to title case as | |
3997 * per {@link Character#toLowerCase(char)}. No other letters are changed.</p> | |
3998 * | |
3999 * @param str the String to uncapitalize, may be null | |
4000 * @return the uncapitalized String, <code>null</code> if null String input | |
4001 * @deprecated Use the standardly named {@link #uncapitalize(String)}. | |
4002 * Method will be removed in Commons Lang 3.0. | |
4003 */ | |
4004 public static String uncapitalise(String str) | |
4005 { | |
4006 return uncapitalize(str); | |
4007 } | |
4008 | |
4009 /** | |
4010 * <p>Swaps the case of a String changing upper and title case to | |
4011 * lower case, and lower case to upper case.</p> | |
4012 * <p/> | |
4013 * <ul> | |
4014 * <li>Upper case character converts to Lower case</li> | |
4015 * <li>Title case character converts to Lower case</li> | |
4016 * <li>Lower case character converts to Upper case</li> | |
4017 * </ul> | |
4018 * <p/> | |
4019 * <p>For a word based algorithm, see {@link WordUtils#swapCase(String)}. | |
4020 * A <code>null</code> input String returns <code>null</code>.</p> | |
4021 * <p/> | |
4022 * <pre> | |
4023 * StringUtils.swapCase(null) = null | |
4024 * StringUtils.swapCase("") = "" | |
4025 * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone" | |
4026 * </pre> | |
4027 * <p/> | |
4028 * <p>NOTE: This method changed in Lang version 2.0. | |
4029 * It no longer performs a word based algorithm. | |
4030 * If you only use ASCII, you will notice no change. | |
4031 * That functionality is available in WordUtils.</p> | |
4032 * | |
4033 * @param str the String to swap case, may be null | |
4034 * @return the changed String, <code>null</code> if null String input | |
4035 */ | |
4036 public static String swapCase(String str) | |
4037 { | |
4038 int strLen; | |
4039 if (str == null || (strLen = str.length()) == 0) | |
4040 { | |
4041 return str; | |
4042 } | |
4043 StringBuffer buffer = new StringBuffer(strLen); | |
4044 | |
4045 char ch = 0; | |
4046 for (int i = 0; i < strLen; i++) | |
4047 { | |
4048 ch = str.charAt(i); | |
4049 if (Character.isUpperCase(ch)) | |
4050 { | |
4051 ch = Character.toLowerCase(ch); | |
4052 } else if (Character.isTitleCase(ch)) | |
4053 { | |
4054 ch = Character.toLowerCase(ch); | |
4055 } else if (Character.isLowerCase(ch)) | |
4056 { | |
4057 ch = Character.toUpperCase(ch); | |
4058 } | |
4059 buffer.append(ch); | |
4060 } | |
4061 return buffer.toString(); | |
4062 } | |
4063 | |
4064 // Count matches | |
4065 //----------------------------------------------------------------------- | |
4066 | |
4067 /** | |
4068 * <p>Counts how many times the substring appears in the larger String.</p> | |
4069 * <p/> | |
4070 * <p>A <code>null</code> or empty ("") String input returns <code>0</code>.</
p> | |
4071 * <p/> | |
4072 * <pre> | |
4073 * StringUtils.countMatches(null, *) = 0 | |
4074 * StringUtils.countMatches("", *) = 0 | |
4075 * StringUtils.countMatches("abba", null) = 0 | |
4076 * StringUtils.countMatches("abba", "") = 0 | |
4077 * StringUtils.countMatches("abba", "a") = 2 | |
4078 * StringUtils.countMatches("abba", "ab") = 1 | |
4079 * StringUtils.countMatches("abba", "xxx") = 0 | |
4080 * </pre> | |
4081 * | |
4082 * @param str the String to check, may be null | |
4083 * @param sub the substring to count, may be null | |
4084 * @return the number of occurrences, 0 if either String is <code>null</code> | |
4085 */ | |
4086 public static int countMatches(String str, String sub) | |
4087 { | |
4088 if (isEmpty(str) || isEmpty(sub)) | |
4089 { | |
4090 return 0; | |
4091 } | |
4092 int count = 0; | |
4093 int idx = 0; | |
4094 while ((idx = str.indexOf(sub, idx)) != -1) | |
4095 { | |
4096 count++; | |
4097 idx += sub.length(); | |
4098 } | |
4099 return count; | |
4100 } | |
4101 | |
4102 // Character Tests | |
4103 //----------------------------------------------------------------------- | |
4104 | |
4105 /** | |
4106 * <p>Checks if the String contains only unicode letters.</p> | |
4107 * <p/> | |
4108 * <p><code>null</code> will return <code>false</code>. | |
4109 * An empty String ("") will return <code>true</code>.</p> | |
4110 * <p/> | |
4111 * <pre> | |
4112 * StringUtils.isAlpha(null) = false | |
4113 * StringUtils.isAlpha("") = true | |
4114 * StringUtils.isAlpha(" ") = false | |
4115 * StringUtils.isAlpha("abc") = true | |
4116 * StringUtils.isAlpha("ab2c") = false | |
4117 * StringUtils.isAlpha("ab-c") = false | |
4118 * </pre> | |
4119 * | |
4120 * @param str the String to check, may be null | |
4121 * @return <code>true</code> if only contains letters, and is non-null | |
4122 */ | |
4123 public static boolean isAlpha(String str) | |
4124 { | |
4125 if (str == null) | |
4126 { | |
4127 return false; | |
4128 } | |
4129 int sz = str.length(); | |
4130 for (int i = 0; i < sz; i++) | |
4131 { | |
4132 if (Character.isLetter(str.charAt(i)) == false) | |
4133 { | |
4134 return false; | |
4135 } | |
4136 } | |
4137 return true; | |
4138 } | |
4139 | |
4140 /** | |
4141 * <p>Checks if the String contains only unicode letters and | |
4142 * space (' ').</p> | |
4143 * <p/> | |
4144 * <p><code>null</code> will return <code>false</code> | |
4145 * An empty String ("") will return <code>true</code>.</p> | |
4146 * <p/> | |
4147 * <pre> | |
4148 * StringUtils.isAlphaSpace(null) = false | |
4149 * StringUtils.isAlphaSpace("") = true | |
4150 * StringUtils.isAlphaSpace(" ") = true | |
4151 * StringUtils.isAlphaSpace("abc") = true | |
4152 * StringUtils.isAlphaSpace("ab c") = true | |
4153 * StringUtils.isAlphaSpace("ab2c") = false | |
4154 * StringUtils.isAlphaSpace("ab-c") = false | |
4155 * </pre> | |
4156 * | |
4157 * @param str the String to check, may be null | |
4158 * @return <code>true</code> if only contains letters and space, | |
4159 * and is non-null | |
4160 */ | |
4161 public static boolean isAlphaSpace(String str) | |
4162 { | |
4163 if (str == null) | |
4164 { | |
4165 return false; | |
4166 } | |
4167 int sz = str.length(); | |
4168 for (int i = 0; i < sz; i++) | |
4169 { | |
4170 if ((Character.isLetter(str.charAt(i)) == false) && (str.charAt(i) != ' ')
) | |
4171 { | |
4172 return false; | |
4173 } | |
4174 } | |
4175 return true; | |
4176 } | |
4177 | |
4178 /** | |
4179 * <p>Checks if the String contains only unicode letters or digits.</p> | |
4180 * <p/> | |
4181 * <p><code>null</code> will return <code>false</code>. | |
4182 * An empty String ("") will return <code>true</code>.</p> | |
4183 * <p/> | |
4184 * <pre> | |
4185 * StringUtils.isAlphanumeric(null) = false | |
4186 * StringUtils.isAlphanumeric("") = true | |
4187 * StringUtils.isAlphanumeric(" ") = false | |
4188 * StringUtils.isAlphanumeric("abc") = true | |
4189 * StringUtils.isAlphanumeric("ab c") = false | |
4190 * StringUtils.isAlphanumeric("ab2c") = true | |
4191 * StringUtils.isAlphanumeric("ab-c") = false | |
4192 * </pre> | |
4193 * | |
4194 * @param str the String to check, may be null | |
4195 * @return <code>true</code> if only contains letters or digits, | |
4196 * and is non-null | |
4197 */ | |
4198 public static boolean isAlphanumeric(String str) | |
4199 { | |
4200 if (str == null) | |
4201 { | |
4202 return false; | |
4203 } | |
4204 int sz = str.length(); | |
4205 for (int i = 0; i < sz; i++) | |
4206 { | |
4207 if (Character.isLetterOrDigit(str.charAt(i)) == false) | |
4208 { | |
4209 return false; | |
4210 } | |
4211 } | |
4212 return true; | |
4213 } | |
4214 | |
4215 /** | |
4216 * <p>Checks if the String contains only unicode letters, digits | |
4217 * or space (<code>' '</code>).</p> | |
4218 * <p/> | |
4219 * <p><code>null</code> will return <code>false</code>. | |
4220 * An empty String ("") will return <code>true</code>.</p> | |
4221 * <p/> | |
4222 * <pre> | |
4223 * StringUtils.isAlphanumeric(null) = false | |
4224 * StringUtils.isAlphanumeric("") = true | |
4225 * StringUtils.isAlphanumeric(" ") = true | |
4226 * StringUtils.isAlphanumeric("abc") = true | |
4227 * StringUtils.isAlphanumeric("ab c") = true | |
4228 * StringUtils.isAlphanumeric("ab2c") = true | |
4229 * StringUtils.isAlphanumeric("ab-c") = false | |
4230 * </pre> | |
4231 * | |
4232 * @param str the String to check, may be null | |
4233 * @return <code>true</code> if only contains letters, digits or space, | |
4234 * and is non-null | |
4235 */ | |
4236 public static boolean isAlphanumericSpace(String str) | |
4237 { | |
4238 if (str == null) | |
4239 { | |
4240 return false; | |
4241 } | |
4242 int sz = str.length(); | |
4243 for (int i = 0; i < sz; i++) | |
4244 { | |
4245 if ((Character.isLetterOrDigit(str.charAt(i)) == false) && (str.charAt(i)
!= ' ')) | |
4246 { | |
4247 return false; | |
4248 } | |
4249 } | |
4250 return true; | |
4251 } | |
4252 | |
4253 /** | |
4254 * <p>Checks if the string contains only ASCII printable characters.</p> | |
4255 * <p/> | |
4256 * <p><code>null</code> will return <code>false</code>. | |
4257 * An empty String ("") will return <code>true</code>.</p> | |
4258 * <p/> | |
4259 * <pre> | |
4260 * StringUtils.isAsciiPrintable(null) = false | |
4261 * StringUtils.isAsciiPrintable("") = true | |
4262 * StringUtils.isAsciiPrintable(" ") = true | |
4263 * StringUtils.isAsciiPrintable("Ceki") = true | |
4264 * StringUtils.isAsciiPrintable("ab2c") = true | |
4265 * StringUtils.isAsciiPrintable("!ab-c~") = true | |
4266 * StringUtils.isAsciiPrintable("\u0020") = true | |
4267 * StringUtils.isAsciiPrintable("\u0021") = true | |
4268 * StringUtils.isAsciiPrintable("\u007e") = true | |
4269 * StringUtils.isAsciiPrintable("\u007f") = false | |
4270 * StringUtils.isAsciiPrintable("Ceki G\u00fclc\u00fc") = false | |
4271 * </pre> | |
4272 * | |
4273 * @param str the string to check, may be null | |
4274 * @return <code>true</code> if every character is in the range | |
4275 * 32 thru 126 | |
4276 * @since 2.1 | |
4277 */ | |
4278 public static boolean isAsciiPrintable(String str) | |
4279 { | |
4280 if (str == null) | |
4281 { | |
4282 return false; | |
4283 } | |
4284 int sz = str.length(); | |
4285 for (int i = 0; i < sz; i++) | |
4286 { | |
4287 if (CharUtils.isAsciiPrintable(str.charAt(i)) == false) | |
4288 { | |
4289 return false; | |
4290 } | |
4291 } | |
4292 return true; | |
4293 } | |
4294 | |
4295 /** | |
4296 * <p>Checks if the String contains only unicode digits. | |
4297 * A decimal point is not a unicode digit and returns false.</p> | |
4298 * <p/> | |
4299 * <p><code>null</code> will return <code>false</code>. | |
4300 * An empty String ("") will return <code>true</code>.</p> | |
4301 * <p/> | |
4302 * <pre> | |
4303 * StringUtils.isNumeric(null) = false | |
4304 * StringUtils.isNumeric("") = true | |
4305 * StringUtils.isNumeric(" ") = false | |
4306 * StringUtils.isNumeric("123") = true | |
4307 * StringUtils.isNumeric("12 3") = false | |
4308 * StringUtils.isNumeric("ab2c") = false | |
4309 * StringUtils.isNumeric("12-3") = false | |
4310 * StringUtils.isNumeric("12.3") = false | |
4311 * </pre> | |
4312 * | |
4313 * @param str the String to check, may be null | |
4314 * @return <code>true</code> if only contains digits, and is non-null | |
4315 */ | |
4316 public static boolean isNumeric(String str) | |
4317 { | |
4318 if (str == null) | |
4319 { | |
4320 return false; | |
4321 } | |
4322 int sz = str.length(); | |
4323 for (int i = 0; i < sz; i++) | |
4324 { | |
4325 if (Character.isDigit(str.charAt(i)) == false) | |
4326 { | |
4327 return false; | |
4328 } | |
4329 } | |
4330 return true; | |
4331 } | |
4332 | |
4333 /** | |
4334 * <p>Checks if the String contains only unicode digits or space | |
4335 * (<code>' '</code>). | |
4336 * A decimal point is not a unicode digit and returns false.</p> | |
4337 * <p/> | |
4338 * <p><code>null</code> will return <code>false</code>. | |
4339 * An empty String ("") will return <code>true</code>.</p> | |
4340 * <p/> | |
4341 * <pre> | |
4342 * StringUtils.isNumeric(null) = false | |
4343 * StringUtils.isNumeric("") = true | |
4344 * StringUtils.isNumeric(" ") = true | |
4345 * StringUtils.isNumeric("123") = true | |
4346 * StringUtils.isNumeric("12 3") = true | |
4347 * StringUtils.isNumeric("ab2c") = false | |
4348 * StringUtils.isNumeric("12-3") = false | |
4349 * StringUtils.isNumeric("12.3") = false | |
4350 * </pre> | |
4351 * | |
4352 * @param str the String to check, may be null | |
4353 * @return <code>true</code> if only contains digits or space, | |
4354 * and is non-null | |
4355 */ | |
4356 public static boolean isNumericSpace(String str) | |
4357 { | |
4358 if (str == null) | |
4359 { | |
4360 return false; | |
4361 } | |
4362 int sz = str.length(); | |
4363 for (int i = 0; i < sz; i++) | |
4364 { | |
4365 if ((Character.isDigit(str.charAt(i)) == false) && (str.charAt(i) != ' ')) | |
4366 { | |
4367 return false; | |
4368 } | |
4369 } | |
4370 return true; | |
4371 } | |
4372 | |
4373 /** | |
4374 * <p>Checks if the String contains only whitespace.</p> | |
4375 * <p/> | |
4376 * <p><code>null</code> will return <code>false</code>. | |
4377 * An empty String ("") will return <code>true</code>.</p> | |
4378 * <p/> | |
4379 * <pre> | |
4380 * StringUtils.isWhitespace(null) = false | |
4381 * StringUtils.isWhitespace("") = true | |
4382 * StringUtils.isWhitespace(" ") = true | |
4383 * StringUtils.isWhitespace("abc") = false | |
4384 * StringUtils.isWhitespace("ab2c") = false | |
4385 * StringUtils.isWhitespace("ab-c") = false | |
4386 * </pre> | |
4387 * | |
4388 * @param str the String to check, may be null | |
4389 * @return <code>true</code> if only contains whitespace, and is non-null | |
4390 * @since 2.0 | |
4391 */ | |
4392 public static boolean isWhitespace(String str) | |
4393 { | |
4394 if (str == null) | |
4395 { | |
4396 return false; | |
4397 } | |
4398 int sz = str.length(); | |
4399 for (int i = 0; i < sz; i++) | |
4400 { | |
4401 if ((Character.isWhitespace(str.charAt(i)) == false)) | |
4402 { | |
4403 return false; | |
4404 } | |
4405 } | |
4406 return true; | |
4407 } | |
4408 | |
4409 // Defaults | |
4410 //----------------------------------------------------------------------- | |
4411 | |
4412 /** | |
4413 * <p>Returns either the passed in String, | |
4414 * or if the String is <code>null</code>, an empty String ("").</p> | |
4415 * <p/> | |
4416 * <pre> | |
4417 * StringUtils.defaultString(null) = "" | |
4418 * StringUtils.defaultString("") = "" | |
4419 * StringUtils.defaultString("bat") = "bat" | |
4420 * </pre> | |
4421 * | |
4422 * @param str the String to check, may be null | |
4423 * @return the passed in String, or the empty String if it | |
4424 * was <code>null</code> | |
4425 * @see ObjectUtils#toString(Object) | |
4426 * @see String#valueOf(Object) | |
4427 */ | |
4428 public static String defaultString(String str) | |
4429 { | |
4430 return str == null ? EMPTY : str; | |
4431 } | |
4432 | |
4433 /** | |
4434 * <p>Returns either the passed in String, or if the String is | |
4435 * <code>null</code>, the value of <code>defaultStr</code>.</p> | |
4436 * <p/> | |
4437 * <pre> | |
4438 * StringUtils.defaultString(null, "NULL") = "NULL" | |
4439 * StringUtils.defaultString("", "NULL") = "" | |
4440 * StringUtils.defaultString("bat", "NULL") = "bat" | |
4441 * </pre> | |
4442 * | |
4443 * @param str the String to check, may be null | |
4444 * @param defaultStr the default String to return | |
4445 * if the input is <code>null</code>, may be null | |
4446 * @return the passed in String, or the default if it was <code>null</code> | |
4447 * @see ObjectUtils#toString(Object, String) | |
4448 * @see String#valueOf(Object) | |
4449 */ | |
4450 public static String defaultString(String str, String defaultStr) | |
4451 { | |
4452 return str == null ? defaultStr : str; | |
4453 } | |
4454 | |
4455 /** | |
4456 * <p>Returns either the passed in String, or if the String is | |
4457 * empty or <code>null</code>, the value of <code>defaultStr</code>.</p> | |
4458 * <p/> | |
4459 * <pre> | |
4460 * StringUtils.defaultIfEmpty(null, "NULL") = "NULL" | |
4461 * StringUtils.defaultIfEmpty("", "NULL") = "NULL" | |
4462 * StringUtils.defaultIfEmpty("bat", "NULL") = "bat" | |
4463 * </pre> | |
4464 * | |
4465 * @param str the String to check, may be null | |
4466 * @param defaultStr the default String to return | |
4467 * if the input is empty ("") or <code>null</code>, may be n
ull | |
4468 * @return the passed in String, or the default | |
4469 * @see StringUtils#defaultString(String, String) | |
4470 */ | |
4471 public static String defaultIfEmpty(String str, String defaultStr) | |
4472 { | |
4473 return StringUtils.isEmpty(str) ? defaultStr : str; | |
4474 } | |
4475 | |
4476 // Reversing | |
4477 //----------------------------------------------------------------------- | |
4478 | |
4479 /** | |
4480 * <p>Reverses a String as per {@link StringBuffer#reverse()}.</p> | |
4481 * <p/> | |
4482 * <p>A <code>null</code> String returns <code>null</code>.</p> | |
4483 * <p/> | |
4484 * <pre> | |
4485 * StringUtils.reverse(null) = null | |
4486 * StringUtils.reverse("") = "" | |
4487 * StringUtils.reverse("bat") = "tab" | |
4488 * </pre> | |
4489 * | |
4490 * @param str the String to reverse, may be null | |
4491 * @return the reversed String, <code>null</code> if null String input | |
4492 */ | |
4493 public static String reverse(String str) | |
4494 { | |
4495 if (str == null) | |
4496 { | |
4497 return null; | |
4498 } | |
4499 return new StringBuffer(str).reverse().toString(); | |
4500 } | |
4501 | |
4502 // Abbreviating | |
4503 //----------------------------------------------------------------------- | |
4504 | |
4505 /** | |
4506 * <p>Abbreviates a String using ellipses. This will turn | |
4507 * "Now is the time for all good men" into "Now is the time for..."</p> | |
4508 * <p/> | |
4509 * <p>Specifically: | |
4510 * <ul> | |
4511 * <li>If <code>str</code> is less than <code>maxWidth</code> characters | |
4512 * long, return it.</li> | |
4513 * <li>Else abbreviate it to <code>(substring(str, 0, max-3) + "...")</code>.<
/li> | |
4514 * <li>If <code>maxWidth</code> is less than <code>4</code>, throw an | |
4515 * <code>IllegalArgumentException</code>.</li> | |
4516 * <li>In no case will it return a String of length greater than | |
4517 * <code>maxWidth</code>.</li> | |
4518 * </ul> | |
4519 * </p> | |
4520 * <p/> | |
4521 * <pre> | |
4522 * StringUtils.abbreviate(null, *) = null | |
4523 * StringUtils.abbreviate("", 4) = "" | |
4524 * StringUtils.abbreviate("abcdefg", 6) = "abc..." | |
4525 * StringUtils.abbreviate("abcdefg", 7) = "abcdefg" | |
4526 * StringUtils.abbreviate("abcdefg", 8) = "abcdefg" | |
4527 * StringUtils.abbreviate("abcdefg", 4) = "a..." | |
4528 * StringUtils.abbreviate("abcdefg", 3) = IllegalArgumentException | |
4529 * </pre> | |
4530 * | |
4531 * @param str the String to check, may be null | |
4532 * @param maxWidth maximum length of result String, must be at least 4 | |
4533 * @return abbreviated String, <code>null</code> if null String input | |
4534 * @throws IllegalArgumentException if the width is too small | |
4535 * @since 2.0 | |
4536 */ | |
4537 public static String abbreviate(String str, int maxWidth) | |
4538 { | |
4539 return abbreviate(str, 0, maxWidth); | |
4540 } | |
4541 | |
4542 /** | |
4543 * <p>Abbreviates a String using ellipses. This will turn | |
4544 * "Now is the time for all good men" into "...is the time for..."</p> | |
4545 * <p/> | |
4546 * <p>Works like <code>abbreviate(String, int)</code>, but allows you to speci
fy | |
4547 * a "left edge" offset. Note that this left edge is not necessarily going to | |
4548 * be the leftmost character in the result, or the first character following t
he | |
4549 * ellipses, but it will appear somewhere in the result. | |
4550 * <p/> | |
4551 * <p>In no case will it return a String of length greater than | |
4552 * <code>maxWidth</code>.</p> | |
4553 * <p/> | |
4554 * <pre> | |
4555 * StringUtils.abbreviate(null, *, *) = null | |
4556 * StringUtils.abbreviate("", 0, 4) = "" | |
4557 * StringUtils.abbreviate("abcdefghijklmno", -1, 10) = "abcdefg..." | |
4558 * StringUtils.abbreviate("abcdefghijklmno", 0, 10) = "abcdefg..." | |
4559 * StringUtils.abbreviate("abcdefghijklmno", 1, 10) = "abcdefg..." | |
4560 * StringUtils.abbreviate("abcdefghijklmno", 4, 10) = "abcdefg..." | |
4561 * StringUtils.abbreviate("abcdefghijklmno", 5, 10) = "...fghi..." | |
4562 * StringUtils.abbreviate("abcdefghijklmno", 6, 10) = "...ghij..." | |
4563 * StringUtils.abbreviate("abcdefghijklmno", 8, 10) = "...ijklmno" | |
4564 * StringUtils.abbreviate("abcdefghijklmno", 10, 10) = "...ijklmno" | |
4565 * StringUtils.abbreviate("abcdefghijklmno", 12, 10) = "...ijklmno" | |
4566 * StringUtils.abbreviate("abcdefghij", 0, 3) = IllegalArgumentExceptio
n | |
4567 * StringUtils.abbreviate("abcdefghij", 5, 6) = IllegalArgumentExceptio
n | |
4568 * </pre> | |
4569 * | |
4570 * @param str the String to check, may be null | |
4571 * @param offset left edge of source String | |
4572 * @param maxWidth maximum length of result String, must be at least 4 | |
4573 * @return abbreviated String, <code>null</code> if null String input | |
4574 * @throws IllegalArgumentException if the width is too small | |
4575 * @since 2.0 | |
4576 */ | |
4577 public static String abbreviate(String str, int offset, int maxWidth) | |
4578 { | |
4579 if (str == null) | |
4580 { | |
4581 return null; | |
4582 } | |
4583 if (maxWidth < 4) | |
4584 { | |
4585 throw new IllegalArgumentException("Minimum abbreviation width is 4"); | |
4586 } | |
4587 if (str.length() <= maxWidth) | |
4588 { | |
4589 return str; | |
4590 } | |
4591 if (offset > str.length()) | |
4592 { | |
4593 offset = str.length(); | |
4594 } | |
4595 if ((str.length() - offset) < (maxWidth - 3)) | |
4596 { | |
4597 offset = str.length() - (maxWidth - 3); | |
4598 } | |
4599 if (offset <= 4) | |
4600 { | |
4601 return str.substring(0, maxWidth - 3) + "..."; | |
4602 } | |
4603 if (maxWidth < 7) | |
4604 { | |
4605 throw new IllegalArgumentException("Minimum abbreviation width with offset
is 7"); | |
4606 } | |
4607 if ((offset + (maxWidth - 3)) < str.length()) | |
4608 { | |
4609 return "..." + abbreviate(str.substring(offset), maxWidth - 3); | |
4610 } | |
4611 return "..." + str.substring(str.length() - (maxWidth - 3)); | |
4612 } | |
4613 | |
4614 // Difference | |
4615 //----------------------------------------------------------------------- | |
4616 | |
4617 /** | |
4618 * <p>Compares two Strings, and returns the portion where they differ. | |
4619 * (More precisely, return the remainder of the second String, | |
4620 * starting from where it's different from the first.)</p> | |
4621 * <p/> | |
4622 * <p>For example, | |
4623 * <code>difference("i am a machine", "i am a robot") -> "robot"</code>.</p> | |
4624 * <p/> | |
4625 * <pre> | |
4626 * StringUtils.difference(null, null) = null | |
4627 * StringUtils.difference("", "") = "" | |
4628 * StringUtils.difference("", "abc") = "abc" | |
4629 * StringUtils.difference("abc", "") = "" | |
4630 * StringUtils.difference("abc", "abc") = "" | |
4631 * StringUtils.difference("ab", "abxyz") = "xyz" | |
4632 * StringUtils.difference("abcde", "abxyz") = "xyz" | |
4633 * StringUtils.difference("abcde", "xyz") = "xyz" | |
4634 * </pre> | |
4635 * | |
4636 * @param str1 the first String, may be null | |
4637 * @param str2 the second String, may be null | |
4638 * @return the portion of str2 where it differs from str1; returns the | |
4639 * empty String if they are equal | |
4640 * @since 2.0 | |
4641 */ | |
4642 public static String difference(String str1, String str2) | |
4643 { | |
4644 if (str1 == null) | |
4645 { | |
4646 return str2; | |
4647 } | |
4648 if (str2 == null) | |
4649 { | |
4650 return str1; | |
4651 } | |
4652 int at = indexOfDifference(str1, str2); | |
4653 if (at == -1) | |
4654 { | |
4655 return EMPTY; | |
4656 } | |
4657 return str2.substring(at); | |
4658 } | |
4659 | |
4660 /** | |
4661 * <p>Compares two Strings, and returns the index at which the | |
4662 * Strings begin to differ.</p> | |
4663 * <p/> | |
4664 * <p>For example, | |
4665 * <code>indexOfDifference("i am a machine", "i am a robot") -> 7</code></p> | |
4666 * <p/> | |
4667 * <pre> | |
4668 * StringUtils.indexOfDifference(null, null) = -1 | |
4669 * StringUtils.indexOfDifference("", "") = -1 | |
4670 * StringUtils.indexOfDifference("", "abc") = 0 | |
4671 * StringUtils.indexOfDifference("abc", "") = 0 | |
4672 * StringUtils.indexOfDifference("abc", "abc") = -1 | |
4673 * StringUtils.indexOfDifference("ab", "abxyz") = 2 | |
4674 * StringUtils.indexOfDifference("abcde", "abxyz") = 2 | |
4675 * StringUtils.indexOfDifference("abcde", "xyz") = 0 | |
4676 * </pre> | |
4677 * | |
4678 * @param str1 the first String, may be null | |
4679 * @param str2 the second String, may be null | |
4680 * @return the index where str2 and str1 begin to differ; -1 if they are equal | |
4681 * @since 2.0 | |
4682 */ | |
4683 public static int indexOfDifference(String str1, String str2) | |
4684 { | |
4685 if (str1 == str2) | |
4686 { | |
4687 return -1; | |
4688 } | |
4689 if (str1 == null || str2 == null) | |
4690 { | |
4691 return 0; | |
4692 } | |
4693 int i; | |
4694 for (i = 0; i < str1.length() && i < str2.length(); ++i) | |
4695 { | |
4696 if (str1.charAt(i) != str2.charAt(i)) | |
4697 { | |
4698 break; | |
4699 } | |
4700 } | |
4701 if (i < str2.length() || i < str1.length()) | |
4702 { | |
4703 return i; | |
4704 } | |
4705 return -1; | |
4706 } | |
4707 | |
4708 /** | |
4709 * <p>Compares all Strings in an array and returns the index at which the | |
4710 * Strings begin to differ.</p> | |
4711 * <p/> | |
4712 * <p>For example, | |
4713 * <code>indexOfDifference(new String[] {"i am a machine", "i am a robot"}) ->
7</code></p> | |
4714 * <p/> | |
4715 * <pre> | |
4716 * StringUtils.indexOfDifference(null) = -1 | |
4717 * StringUtils.indexOfDifference(new String[] {}) = -1 | |
4718 * StringUtils.indexOfDifference(new String[] {"abc"}) = -1 | |
4719 * StringUtils.indexOfDifference(new String[] {null, null}) = -1 | |
4720 * StringUtils.indexOfDifference(new String[] {"", ""}) = -1 | |
4721 * StringUtils.indexOfDifference(new String[] {"", null}) = 0 | |
4722 * StringUtils.indexOfDifference(new String[] {"abc", null, null}) = 0 | |
4723 * StringUtils.indexOfDifference(new String[] {null, null, "abc"}) = 0 | |
4724 * StringUtils.indexOfDifference(new String[] {"", "abc"}) = 0 | |
4725 * StringUtils.indexOfDifference(new String[] {"abc", ""}) = 0 | |
4726 * StringUtils.indexOfDifference(new String[] {"abc", "abc"}) = -1 | |
4727 * StringUtils.indexOfDifference(new String[] {"abc", "a"}) = 1 | |
4728 * StringUtils.indexOfDifference(new String[] {"ab", "abxyz"}) = 2 | |
4729 * StringUtils.indexOfDifference(new String[] {"abcde", "abxyz"}) = 2 | |
4730 * StringUtils.indexOfDifference(new String[] {"abcde", "xyz"}) = 0 | |
4731 * StringUtils.indexOfDifference(new String[] {"xyz", "abcde"}) = 0 | |
4732 * StringUtils.indexOfDifference(new String[] {"i am a machine", "i am a robot
"}) = 7 | |
4733 * </pre> | |
4734 * | |
4735 * @param strs array of strings, entries may be null | |
4736 * @return the index where the strings begin to differ; -1 if they are all equ
al | |
4737 * @since 2.4 | |
4738 */ | |
4739 public static int indexOfDifference(String[] strs) | |
4740 { | |
4741 if (strs == null || strs.length <= 1) | |
4742 { | |
4743 return -1; | |
4744 } | |
4745 boolean anyStringNull = false; | |
4746 boolean allStringsNull = true; | |
4747 int arrayLen = strs.length; | |
4748 int shortestStrLen = Integer.MAX_VALUE; | |
4749 int longestStrLen = 0; | |
4750 | |
4751 // find the min and max string lengths; this avoids checking to make | |
4752 // sure we are not exceeding the length of the string each time through | |
4753 // the bottom loop. | |
4754 for (int i = 0; i < arrayLen; i++) | |
4755 { | |
4756 if (strs[i] == null) | |
4757 { | |
4758 anyStringNull = true; | |
4759 shortestStrLen = 0; | |
4760 } else | |
4761 { | |
4762 allStringsNull = false; | |
4763 shortestStrLen = Math.min(strs[i].length(), shortestStrLen); | |
4764 longestStrLen = Math.max(strs[i].length(), longestStrLen); | |
4765 } | |
4766 } | |
4767 | |
4768 // handle lists containing all nulls or all empty strings | |
4769 if (allStringsNull || (longestStrLen == 0 && !anyStringNull)) | |
4770 { | |
4771 return -1; | |
4772 } | |
4773 | |
4774 // handle lists containing some nulls or some empty strings | |
4775 if (shortestStrLen == 0) | |
4776 { | |
4777 return 0; | |
4778 } | |
4779 | |
4780 // find the position with the first difference across all strings | |
4781 int firstDiff = -1; | |
4782 for (int stringPos = 0; stringPos < shortestStrLen; stringPos++) | |
4783 { | |
4784 char comparisonChar = strs[0].charAt(stringPos); | |
4785 for (int arrayPos = 1; arrayPos < arrayLen; arrayPos++) | |
4786 { | |
4787 if (strs[arrayPos].charAt(stringPos) != comparisonChar) | |
4788 { | |
4789 firstDiff = stringPos; | |
4790 break; | |
4791 } | |
4792 } | |
4793 if (firstDiff != -1) | |
4794 { | |
4795 break; | |
4796 } | |
4797 } | |
4798 | |
4799 if (firstDiff == -1 && shortestStrLen != longestStrLen) | |
4800 { | |
4801 // we compared all of the characters up to the length of the | |
4802 // shortest string and didn't find a match, but the string lengths | |
4803 // vary, so return the length of the shortest string. | |
4804 return shortestStrLen; | |
4805 } | |
4806 return firstDiff; | |
4807 } | |
4808 | |
4809 /** | |
4810 * <p>Compares all Strings in an array and returns the initial sequence of | |
4811 * characters that is common to all of them.</p> | |
4812 * <p/> | |
4813 * <p>For example, | |
4814 * <code>getCommonPrefix(new String[] {"i am a machine", "i am a robot"}) -> "
i am a "</code></p> | |
4815 * <p/> | |
4816 * <pre> | |
4817 * StringUtils.getCommonPrefix(null) = "" | |
4818 * StringUtils.getCommonPrefix(new String[] {}) = "" | |
4819 * StringUtils.getCommonPrefix(new String[] {"abc"}) = "abc" | |
4820 * StringUtils.getCommonPrefix(new String[] {null, null}) = "" | |
4821 * StringUtils.getCommonPrefix(new String[] {"", ""}) = "" | |
4822 * StringUtils.getCommonPrefix(new String[] {"", null}) = "" | |
4823 * StringUtils.getCommonPrefix(new String[] {"abc", null, null}) = "" | |
4824 * StringUtils.getCommonPrefix(new String[] {null, null, "abc"}) = "" | |
4825 * StringUtils.getCommonPrefix(new String[] {"", "abc"}) = "" | |
4826 * StringUtils.getCommonPrefix(new String[] {"abc", ""}) = "" | |
4827 * StringUtils.getCommonPrefix(new String[] {"abc", "abc"}) = "abc" | |
4828 * StringUtils.getCommonPrefix(new String[] {"abc", "a"}) = "a" | |
4829 * StringUtils.getCommonPrefix(new String[] {"ab", "abxyz"}) = "ab" | |
4830 * StringUtils.getCommonPrefix(new String[] {"abcde", "abxyz"}) = "ab" | |
4831 * StringUtils.getCommonPrefix(new String[] {"abcde", "xyz"}) = "" | |
4832 * StringUtils.getCommonPrefix(new String[] {"xyz", "abcde"}) = "" | |
4833 * StringUtils.getCommonPrefix(new String[] {"i am a machine", "i am a robot"}
) = "i am a " | |
4834 * </pre> | |
4835 * | |
4836 * @param strs array of String objects, entries may be null | |
4837 * @return the initial sequence of characters that are common to all Strings | |
4838 * in the array; empty String if the array is null, the elements are all null | |
4839 * or if there is no common prefix. | |
4840 * @since 2.4 | |
4841 */ | |
4842 public static String getCommonPrefix(String[] strs) | |
4843 { | |
4844 if (strs == null || strs.length == 0) | |
4845 { | |
4846 return EMPTY; | |
4847 } | |
4848 int smallestIndexOfDiff = indexOfDifference(strs); | |
4849 if (smallestIndexOfDiff == -1) | |
4850 { | |
4851 // all strings were identical | |
4852 if (strs[0] == null) | |
4853 { | |
4854 return EMPTY; | |
4855 } | |
4856 return strs[0]; | |
4857 } else if (smallestIndexOfDiff == 0) | |
4858 { | |
4859 // there were no common initial characters | |
4860 return EMPTY; | |
4861 } else | |
4862 { | |
4863 // we found a common initial character sequence | |
4864 return strs[0].substring(0, smallestIndexOfDiff); | |
4865 } | |
4866 } | |
4867 | |
4868 // Misc | |
4869 //----------------------------------------------------------------------- | |
4870 | |
4871 /** | |
4872 * <p>Find the Levenshtein distance between two Strings.</p> | |
4873 * <p/> | |
4874 * <p>This is the number of changes needed to change one String into | |
4875 * another, where each change is a single character modification (deletion, | |
4876 * insertion or substitution).</p> | |
4877 * <p/> | |
4878 * <p>The previous implementation of the Levenshtein distance algorithm | |
4879 * was from <a href="http://www.merriampark.com/ld.htm">http://www.merriampark
.com/ld.htm</a></p> | |
4880 * <p/> | |
4881 * <p>Chas Emerick has written an implementation in Java, which avoids an OutO
fMemoryError | |
4882 * which can occur when my Java implementation is used with very large strings
.<br> | |
4883 * This implementation of the Levenshtein distance algorithm | |
4884 * is from <a href="http://www.merriampark.com/ldjava.htm">http://www.merriamp
ark.com/ldjava.htm</a></p> | |
4885 * <p/> | |
4886 * <pre> | |
4887 * StringUtils.getLevenshteinDistance(null, *) = IllegalArgumentEx
ception | |
4888 * StringUtils.getLevenshteinDistance(*, null) = IllegalArgumentEx
ception | |
4889 * StringUtils.getLevenshteinDistance("","") = 0 | |
4890 * StringUtils.getLevenshteinDistance("","a") = 1 | |
4891 * StringUtils.getLevenshteinDistance("aaapppp", "") = 7 | |
4892 * StringUtils.getLevenshteinDistance("frog", "fog") = 1 | |
4893 * StringUtils.getLevenshteinDistance("fly", "ant") = 3 | |
4894 * StringUtils.getLevenshteinDistance("elephant", "hippo") = 7 | |
4895 * StringUtils.getLevenshteinDistance("hippo", "elephant") = 7 | |
4896 * StringUtils.getLevenshteinDistance("hippo", "zzzzzzzz") = 8 | |
4897 * StringUtils.getLevenshteinDistance("hello", "hallo") = 1 | |
4898 * </pre> | |
4899 * | |
4900 * @param s the first String, must not be null | |
4901 * @param t the second String, must not be null | |
4902 * @return result distance | |
4903 * @throws IllegalArgumentException if either String input <code>null</code> | |
4904 */ | |
4905 public static int getLevenshteinDistance(String s, String t) | |
4906 { | |
4907 if (s == null || t == null) | |
4908 { | |
4909 throw new IllegalArgumentException("Strings must not be null"); | |
4910 } | |
4911 | |
4912 /* | |
4913 The difference between this impl. and the previous is that, rather | |
4914 than creating and retaining a matrix of size s.length()+1 by t.length
()+1, | |
4915 we maintain two single-dimensional arrays of length s.length()+1. Th
e first, d, | |
4916 is the 'current working' distance array that maintains the newest dis
tance cost | |
4917 counts as we iterate through the characters of String s. Each time w
e increment | |
4918 the index of String t we are comparing, d is copied to p, the second
int[]. Doing so | |
4919 allows us to retain the previous cost counts as required by the algor
ithm (taking | |
4920 the minimum of the cost count to the left, up one, and diagonally up
and to the left | |
4921 of the current cost count being calculated). (Note that the arrays a
ren't really | |
4922 copied anymore, just switched...this is clearly much better than clon
ing an array | |
4923 or doing a System.arraycopy() each time through the outer loop.) | |
4924 | |
4925 Effectively, the difference between the two implementations is this o
ne does not | |
4926 cause an out of memory condition when calculating the LD over two ver
y large strings. | |
4927 */ | |
4928 | |
4929 int n = s.length(); // length of s | |
4930 int m = t.length(); // length of t | |
4931 | |
4932 if (n == 0) | |
4933 { | |
4934 return m; | |
4935 } else if (m == 0) | |
4936 { | |
4937 return n; | |
4938 } | |
4939 | |
4940 if (n > m) | |
4941 { | |
4942 // swap the input strings to consume less memory | |
4943 String tmp = s; | |
4944 s = t; | |
4945 t = tmp; | |
4946 n = m; | |
4947 m = t.length(); | |
4948 } | |
4949 | |
4950 int p[] = new int[n + 1]; //'previous' cost array, horizontally | |
4951 int d[] = new int[n + 1]; // cost array, horizontally | |
4952 int _d[]; //placeholder to assist in swapping p and d | |
4953 | |
4954 // indexes into strings s and t | |
4955 int i; // iterates through s | |
4956 int j; // iterates through t | |
4957 | |
4958 char t_j; // jth character of t | |
4959 | |
4960 int cost; // cost | |
4961 | |
4962 for (i = 0; i <= n; i++) | |
4963 { | |
4964 p[i] = i; | |
4965 } | |
4966 | |
4967 for (j = 1; j <= m; j++) | |
4968 { | |
4969 t_j = t.charAt(j - 1); | |
4970 d[0] = j; | |
4971 | |
4972 for (i = 1; i <= n; i++) | |
4973 { | |
4974 cost = s.charAt(i - 1) == t_j ? 0 : 1; | |
4975 // minimum of cell to the left+1, to the top+1, diagonally left and up +
cost | |
4976 d[i] = Math.min(Math.min(d[i - 1] + 1, p[i] + 1), p[i - 1] + cost); | |
4977 } | |
4978 | |
4979 // copy current distance counts to 'previous row' distance counts | |
4980 _d = p; | |
4981 p = d; | |
4982 d = _d; | |
4983 } | |
4984 | |
4985 // our last action in the above loop was to switch d and p, so p now | |
4986 // actually has the most recent cost counts | |
4987 return p[n]; | |
4988 } | |
4989 | |
4990 /** | |
4991 * <p>Gets the minimum of three <code>int</code> values.</p> | |
4992 * | |
4993 * @param a value 1 | |
4994 * @param b value 2 | |
4995 * @param c value 3 | |
4996 * @return the smallest of the values | |
4997 */ | |
4998 /* | |
4999 private static int min(int a, int b, int c) { | |
5000 // Method copied from NumberUtils to avoid dependency on subpackage | |
5001 if (b < a) { | |
5002 a = b; | |
5003 } | |
5004 if (c < a) { | |
5005 a = c; | |
5006 } | |
5007 return a; | |
5008 } | |
5009 */ | |
5010 | |
5011 // startsWith | |
5012 //----------------------------------------------------------------------- | |
5013 | |
5014 /** | |
5015 * <p>Check if a String starts with a specified prefix.</p> | |
5016 * <p/> | |
5017 * <p><code>null</code>s are handled without exceptions. Two <code>null</code> | |
5018 * references are considered to be equal. The comparison is case sensitive.</p
> | |
5019 * <p/> | |
5020 * <pre> | |
5021 * StringUtils.startsWith(null, null) = true | |
5022 * StringUtils.startsWith(null, "abcdef") = false | |
5023 * StringUtils.startsWith("abc", null) = false | |
5024 * StringUtils.startsWith("abc", "abcdef") = true | |
5025 * StringUtils.startsWith("abc", "ABCDEF") = false | |
5026 * </pre> | |
5027 * | |
5028 * @param str the String to check, may be null | |
5029 * @param prefix the prefix to find, may be null | |
5030 * @return <code>true</code> if the String starts with the prefix, case sensit
ive, or | |
5031 * both <code>null</code> | |
5032 * @see java.lang.String#startsWith(String) | |
5033 * @since 2.4 | |
5034 */ | |
5035 public static boolean startsWith(String str, String prefix) | |
5036 { | |
5037 return startsWith(str, prefix, false); | |
5038 } | |
5039 | |
5040 /** | |
5041 * <p>Case insensitive check if a String starts with a specified prefix.</p> | |
5042 * <p/> | |
5043 * <p><code>null</code>s are handled without exceptions. Two <code>null</code> | |
5044 * references are considered to be equal. The comparison is case insensitive.<
/p> | |
5045 * <p/> | |
5046 * <pre> | |
5047 * StringUtils.startsWithIgnoreCase(null, null) = true | |
5048 * StringUtils.startsWithIgnoreCase(null, "abcdef") = false | |
5049 * StringUtils.startsWithIgnoreCase("abc", null) = false | |
5050 * StringUtils.startsWithIgnoreCase("abc", "abcdef") = true | |
5051 * StringUtils.startsWithIgnoreCase("abc", "ABCDEF") = true | |
5052 * </pre> | |
5053 * | |
5054 * @param str the String to check, may be null | |
5055 * @param prefix the prefix to find, may be null | |
5056 * @return <code>true</code> if the String starts with the prefix, case insens
itive, or | |
5057 * both <code>null</code> | |
5058 * @see java.lang.String#startsWith(String) | |
5059 * @since 2.4 | |
5060 */ | |
5061 public static boolean startsWithIgnoreCase(String str, String prefix) | |
5062 { | |
5063 return startsWith(str, prefix, true); | |
5064 } | |
5065 | |
5066 /** | |
5067 * <p>Check if a String starts with a specified prefix (optionally case insens
itive).</p> | |
5068 * | |
5069 * @param str the String to check, may be null | |
5070 * @param prefix the prefix to find, may be null | |
5071 * @param ignoreCase inidicates whether the compare should ignore case | |
5072 * (case insensitive) or not. | |
5073 * @return <code>true</code> if the String starts with the prefix or | |
5074 * both <code>null</code> | |
5075 * @see java.lang.String#startsWith(String) | |
5076 */ | |
5077 private static boolean startsWith(String str, String prefix, boolean ignoreCas
e) | |
5078 { | |
5079 if (str == null || prefix == null) | |
5080 { | |
5081 return (str == null && prefix == null); | |
5082 } | |
5083 if (prefix.length() > str.length()) | |
5084 { | |
5085 return false; | |
5086 } | |
5087 return str.regionMatches(ignoreCase, 0, prefix, 0, prefix.length()); | |
5088 } | |
5089 | |
5090 // endsWith | |
5091 //----------------------------------------------------------------------- | |
5092 | |
5093 /** | |
5094 * <p>Check if a String ends with a specified suffix.</p> | |
5095 * <p/> | |
5096 * <p><code>null</code>s are handled without exceptions. Two <code>null</code> | |
5097 * references are considered to be equal. The comparison is case sensitive.</p
> | |
5098 * <p/> | |
5099 * <pre> | |
5100 * StringUtils.endsWith(null, null) = true | |
5101 * StringUtils.endsWith(null, "abcdef") = false | |
5102 * StringUtils.endsWith("def", null) = false | |
5103 * StringUtils.endsWith("def", "abcdef") = true | |
5104 * StringUtils.endsWith("def", "ABCDEF") = false | |
5105 * </pre> | |
5106 * | |
5107 * @param str the String to check, may be null | |
5108 * @param suffix the suffix to find, may be null | |
5109 * @return <code>true</code> if the String ends with the suffix, case sensitiv
e, or | |
5110 * both <code>null</code> | |
5111 * @see java.lang.String#endsWith(String) | |
5112 * @since 2.4 | |
5113 */ | |
5114 public static boolean endsWith(String str, String suffix) | |
5115 { | |
5116 return endsWith(str, suffix, false); | |
5117 } | |
5118 | |
5119 /** | |
5120 * <p>Case insensitive check if a String ends with a specified suffix.</p> | |
5121 * <p/> | |
5122 * <p><code>null</code>s are handled without exceptions. Two <code>null</code> | |
5123 * references are considered to be equal. The comparison is case insensitive.<
/p> | |
5124 * <p/> | |
5125 * <pre> | |
5126 * StringUtils.endsWithIgnoreCase(null, null) = true | |
5127 * StringUtils.endsWithIgnoreCase(null, "abcdef") = false | |
5128 * StringUtils.endsWithIgnoreCase("def", null) = false | |
5129 * StringUtils.endsWithIgnoreCase("def", "abcdef") = true | |
5130 * StringUtils.endsWithIgnoreCase("def", "ABCDEF") = false | |
5131 * </pre> | |
5132 * | |
5133 * @param str the String to check, may be null | |
5134 * @param suffix the suffix to find, may be null | |
5135 * @return <code>true</code> if the String ends with the suffix, case insensit
ive, or | |
5136 * both <code>null</code> | |
5137 * @see java.lang.String#endsWith(String) | |
5138 * @since 2.4 | |
5139 */ | |
5140 public static boolean endsWithIgnoreCase(String str, String suffix) | |
5141 { | |
5142 return endsWith(str, suffix, true); | |
5143 } | |
5144 | |
5145 /** | |
5146 * <p>Check if a String ends with a specified suffix (optionally case insensit
ive).</p> | |
5147 * | |
5148 * @param str the String to check, may be null | |
5149 * @param suffix the suffix to find, may be null | |
5150 * @param ignoreCase inidicates whether the compare should ignore case | |
5151 * (case insensitive) or not. | |
5152 * @return <code>true</code> if the String starts with the prefix or | |
5153 * both <code>null</code> | |
5154 * @see java.lang.String#endsWith(String) | |
5155 */ | |
5156 private static boolean endsWith(String str, String suffix, boolean ignoreCase) | |
5157 { | |
5158 if (str == null || suffix == null) | |
5159 { | |
5160 return (str == null && suffix == null); | |
5161 } | |
5162 if (suffix.length() > str.length()) | |
5163 { | |
5164 return false; | |
5165 } | |
5166 int strOffset = str.length() - suffix.length(); | |
5167 return str.regionMatches(ignoreCase, strOffset, suffix, 0, suffix.length()); | |
5168 } | |
5169 | |
5170 } | |
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