| /* | 
 |  * Copyright 2018 The Android Open Source Project | 
 |  * | 
 |  * Licensed under the Apache License, Version 2.0 (the "License"); | 
 |  * you may not use this file except in compliance with the License. | 
 |  * You may obtain a copy of the License at | 
 |  * | 
 |  *      http://www.apache.org/licenses/LICENSE-2.0 | 
 |  * | 
 |  * Unless required by applicable law or agreed to in writing, software | 
 |  * distributed under the License is distributed on an "AS IS" BASIS, | 
 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
 |  * See the License for the specific language governing permissions and | 
 |  * limitations under the License. | 
 |  */ | 
 |  | 
 | #ifndef JAVA_VM_HELPER_H_ | 
 |  | 
 | #define JAVA_VM_HELPER_H_ | 
 |  | 
 | #include "jni.h" | 
 |  | 
 | #include <atomic> | 
 |  | 
 | namespace android { | 
 |  | 
 | struct JavaVMHelper { | 
 |     static JNIEnv *getJNIEnv(); | 
 |     static void setJavaVM(JavaVM *vm); | 
 |  | 
 | private: | 
 |     // Once a valid JavaVM has been set, it should never be reset or changed. | 
 |     // However, as it may be accessed from multiple threads, access needs to be | 
 |     // synchronized. | 
 |     static std::atomic<JavaVM *> sJavaVM; | 
 | }; | 
 |  | 
 | }  // namespace android | 
 |  | 
 | #endif  // JAVA_VM_HELPER_H_ |