blob: 24a62125439f99a79b68c5bd0335cecaefa3ab20 [file] [log] [blame]
/*
* Copyright 2017 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "sdk/android/src/jni/jni_generator_helper.h"
#include "rtc_base/atomicops.h"
#include "sdk/android/native_api/jni/class_loader.h"
namespace webrtc {
// If |atomic_class_id| set, it'll return immediately. Otherwise, it will look
// up the class and store it. If there's a race, we take care to only store one
// global reference (and the duplicated effort will happen only once).
jclass LazyGetClass(JNIEnv* env,
const char* class_name,
std::atomic<jclass>* atomic_class_id) {
const jclass value = std::atomic_load(atomic_class_id);
if (value)
return value;
webrtc::ScopedJavaGlobalRef<jclass> clazz(webrtc::GetClass(env, class_name));
RTC_CHECK(!clazz.is_null()) << class_name;
jclass cas_result = nullptr;
if (std::atomic_compare_exchange_strong(atomic_class_id, &cas_result,
clazz.obj())) {
// We sucessfully stored |clazz| in |atomic_class_id|, so we are
// intentionally leaking the global ref since it's now stored there.
return clazz.Release();
} else {
// Some other thread came before us and stored a global pointer in
// |atomic_class_id|. Relase our global ref and return the ref from the
// other thread.
return cas_result;
}
}
// If |atomic_method_id| set, it'll return immediately. Otherwise, it will look
// up the method id and store it. If there's a race, it's ok since the values
// are the same (and the duplicated effort will happen only once).
template <MethodID::Type type>
jmethodID MethodID::LazyGet(JNIEnv* env,
jclass clazz,
const char* method_name,
const char* jni_signature,
std::atomic<jmethodID>* atomic_method_id) {
const jmethodID value = std::atomic_load(atomic_method_id);
if (value)
return value;
auto get_method_ptr = type == MethodID::TYPE_STATIC
? &JNIEnv::GetStaticMethodID
: &JNIEnv::GetMethodID;
jmethodID id = (env->*get_method_ptr)(clazz, method_name, jni_signature);
CHECK_EXCEPTION(env) << "error during GetMethodID: " << method_name << ", "
<< jni_signature;
RTC_CHECK(id) << method_name << ", " << jni_signature;
std::atomic_store(atomic_method_id, id);
return id;
}
// Various template instantiations.
template jmethodID MethodID::LazyGet<MethodID::TYPE_STATIC>(
JNIEnv* env,
jclass clazz,
const char* method_name,
const char* jni_signature,
std::atomic<jmethodID>* atomic_method_id);
template jmethodID MethodID::LazyGet<MethodID::TYPE_INSTANCE>(
JNIEnv* env,
jclass clazz,
const char* method_name,
const char* jni_signature,
std::atomic<jmethodID>* atomic_method_id);
} // namespace webrtc