1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SCOPED_LOCAL_REF_H_included 18 #define SCOPED_LOCAL_REF_H_included 19 20 #include "JNIHelp.h" 21 22 // A smart pointer that deletes a JNI local reference when it goes out of scope. 23 template<typename T> 24 class ScopedLocalRef { 25 public: ScopedLocalRef(JNIEnv * env,T localRef)26 ScopedLocalRef(JNIEnv* env, T localRef) 27 : mEnv(env), mLocalRef(localRef) 28 { 29 } 30 ~ScopedLocalRef()31 ~ScopedLocalRef() { 32 reset(); 33 } 34 reset()35 void reset() { 36 if (mLocalRef != NULL) { 37 mEnv->DeleteLocalRef(mLocalRef); 38 mLocalRef = NULL; 39 } 40 } 41 get()42 T get() const { 43 return mLocalRef; 44 } 45 46 private: 47 JNIEnv* mEnv; 48 T mLocalRef; 49 50 // Disallow copy and assignment. 51 ScopedLocalRef(const ScopedLocalRef&); 52 void operator=(const ScopedLocalRef&); 53 }; 54 55 #endif // SCOPED_LOCAL_REF_H_included 56