Issue 4231 - Fix unstable FilterEngineTest.testSetRemoveFilterChangeCallback

libadblockplus-android/src/org/adblockplus/libadblockplus/android/AndroidFileSystem.java

Index: libadblockplus-android/src/org/adblockplus/libadblockplus/android/AndroidFileSystem.java
diff --git a/libadblockplus-android/src/org/adblockplus/libadblockplus/android/AndroidFileSystem.java b/libadblockplus-android/src/org/adblockplus/libadblockplus/android/AndroidFileSystem.java
new file mode 100644
index 0000000000000000000000000000000000000000..d1f3bf709a57420890ab7cb909c11ace960a00ab
--- /dev/null
+++ b/libadblockplus-android/src/org/adblockplus/libadblockplus/android/AndroidFileSystem.java
@@ -0,0 +1,140 @@
+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-2017 eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.adblockplus.libadblockplus.android;
+
+import org.adblockplus.libadblockplus.AdblockPlusException;
+import org.adblockplus.libadblockplus.FileSystem;
+import org.adblockplus.libadblockplus.FileSystemUtils;
+
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * AndroidFileSystem is inefficient for production files routines
+ * as C++ streams can't pass JNI layer and be converted into Java streams and vice versa.
+ *
+ * So in case of any stream routines full stream content is read in either C++ or Java side
+ * and it's being passed as bytes array though JNI layer
+ *
+ * AndroidFileSystem is meant to be used in tests mostly
+ *
+ * All paths are considered relative to the base path, or to be absolute
+ * (see `resolve(String path)`) if no base path is set (see `AndroidFileSystem(File basePath)`)
+ */
+public class AndroidFileSystem extends FileSystem
+{
+  private File basePath;
+
+  public File getBasePath()
+  {
+    return basePath;
+  }
+
+  public AndroidFileSystem()
+  {
+  }
+
+  /*
+   * Sets the base path, all paths are considered relative to it.
+   * @param basePath base path
+   */
+  public AndroidFileSystem(File basePath)
+  {
+    this();
+    this.basePath = basePath;
+  }
+
+  @Override
+  public byte[] read(String path)
+  {
+    File file = new File(path);

[anton, 2017/05/29 11:30:03]

Warning: it does not do resolve() just like in DefaultFileSystem.cpp. This is
going to be updated as soon as it's changed in c++

+    if (!file.exists())
+    {
+      return null;
+    }
+
+    try
+    {
+      return FileSystemUtils.readFile(file);
+    }
+    catch (IOException e)
+    {
+      throw new AdblockPlusException(e);
+    }
+  }
+
+  @Override
+  public void write(String path, byte[] data)
+  {
+    File file = new File(path);

[anton, 2017/05/29 11:30:02]

Warning: it does not do resolve() just like in DefaultFileSystem.cpp. This is
going to be updated as soon as it's changed in c++

+    if (file.exists())
+    {
+      file.delete();
+    }
+
+    try
+    {
+      FileSystemUtils.writeFile(file, data);
+    }
+    catch (IOException e)
+    {
+      throw new AdblockPlusException(e);
+    }
+  }
+
+  @Override
+  public void move(String fromPath, String toPath)
+  {
+    File fromFile = new File(fromPath);
+    if (!fromFile.exists())
+      throw new AdblockPlusException("File does not exist: " + fromPath);
+
+    File toFile = new File(toPath);
+    if (!fromFile.renameTo(toFile))
+    {
+      throw new AdblockPlusException("Failed to move " + fromPath + " to " + toFile);
+    }
+  }
+
+  @Override
+  public void remove(String path)
+  {
+    File file = new File(path);
+    if (file.exists())
+    {
+      file.delete();
+    }
+  }
+
+  @Override
+  public StatResult stat(String path)
+  {
+    File file = new File(path);
+    return new StatResult(
+      file.exists(),
+      file.isDirectory(),
+      file.isFile(),
+      file.lastModified());
+  }
+
+  @Override
+  public String resolve(String path)
+  {
+    return (basePath != null ? new File(basePath, path).getAbsolutePath() : path);
+  }
+}