Issue 1848 - Clean up local reference handling

jni/JniJsValue.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 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
@@ skipping 126 matching lines @@
 jobject NewJniJsValue(JNIEnv* env, const AdblockPlus::JsValuePtr& jsValue, jclass jsValueClass)
 {
   if (!jsValue.get())
   {
     return 0;
   }
 
   jclass clazz = jsValueClass ? jsValueClass : env->FindClass(PKG("JsValue"));
   jmethodID ctor = env->GetMethodID(clazz, "<init>", "(J)V");
   jlong ptr = JniPtrToLong(new AdblockPlus::JsValuePtr(jsValue));
-  return env->NewObject(clazz, ctor, ptr);
+  jobject ret = env->NewObject(clazz, ctor, ptr);
+
+  if (!jsValueClass)
+  {
+    env->DeleteLocalRef(clazz);
+  }
+
+  return ret;
 }
 
 AdblockPlus::JsValue* JniGetJsValue(jlong ptr)
 {
   return JniLongToTypePtr<AdblockPlus::JsValuePtr>(ptr)->get();
 }
 
 AdblockPlus::JsValuePtr& JniGetJsValuePtr(jlong ptr)
 {
   return *JniLongToTypePtr<AdblockPlus::JsValuePtr>(ptr);
 }
 
 jobject JniJsValueListToArrayList(JNIEnv* env, AdblockPlus::JsValueList& list)
 {
   jobject arrayList = NewJniArrayList(env);
 
   for (AdblockPlus::JsValueList::iterator it = list.begin(), end = list.end(); it != end; ++it)
   {
-    JniAddObjectToList(env, arrayList, NewJniJsValue(env, *it));
+    JniAddObjectToList(env, arrayList,
+        *JniLocalReference<jobject>(env, NewJniJsValue(env, *it)));
   }
 
   return arrayList;
 }
 
 // TODO: List of functions that lack JNI bindings
 //std::vector<std::string> GetOwnPropertyNames() const;
 //void SetProperty(const std::string& name, const std::string& val);
 //void SetProperty(const std::string& name, int64_t val);
 //void SetProperty(const std::string& name, bool val);
@@ skipping 17 matching lines @@
   { (char*)"asBoolean", (char*)"(J)Z", (void*)JniAsBoolean },
   { (char*)"asList", (char*)"(J)Ljava/util/List;", (void*)JniAsList },
   { (char*)"getProperty", (char*)"(JLjava/lang/String;)" TYP("JsValue"), (void*)JniGetProperty },
   { (char*)"dtor", (char*)"(J)V", (void*)JniDtor }
 };
 
 extern "C" JNIEXPORT void JNICALL Java_org_adblockplus_libadblockplus_JsValue_registerNatives(JNIEnv *env, jclass clazz)
 {
   env->RegisterNatives(clazz, methods, sizeof(methods) / sizeof(methods[0]));
 }