blob: 3f4419af6d2b648174632dd9fa04ed24728ae1b4 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/android/scoped_java_ref.h"
#include "base/android/jni_android.h"
#include "base/android/jni_string.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace base {
namespace android {
namespace {
int g_local_refs = 0;
int g_global_refs = 0;
const JNINativeInterface* g_previous_functions;
jobject NewGlobalRef(JNIEnv* env, jobject obj) {
return g_previous_functions->NewGlobalRef(env, obj);
void DeleteGlobalRef(JNIEnv* env, jobject obj) {
return g_previous_functions->DeleteGlobalRef(env, obj);
jobject NewLocalRef(JNIEnv* env, jobject obj) {
return g_previous_functions->NewLocalRef(env, obj);
void DeleteLocalRef(JNIEnv* env, jobject obj) {
return g_previous_functions->DeleteLocalRef(env, obj);
} // namespace
class ScopedJavaRefTest : public testing::Test {
void SetUp() override {
g_local_refs = 0;
g_global_refs = 0;
JNIEnv* env = AttachCurrentThread();
g_previous_functions = env->functions;
hooked_functions = *g_previous_functions;
env->functions = &hooked_functions;
// We inject our own functions in JNINativeInterface so we can keep track
// of the reference counting ourselves.
hooked_functions.NewGlobalRef = &NewGlobalRef;
hooked_functions.DeleteGlobalRef = &DeleteGlobalRef;
hooked_functions.NewLocalRef = &NewLocalRef;
hooked_functions.DeleteLocalRef = &DeleteLocalRef;
void TearDown() override {
JNIEnv* env = AttachCurrentThread();
env->functions = g_previous_functions;
// From JellyBean release, the instance of this struct provided in JNIEnv is
// read-only, so we deep copy it to allow individual functions to be hooked.
JNINativeInterface hooked_functions;
// The main purpose of this is testing the various conversions compile.
TEST_F(ScopedJavaRefTest, Conversions) {
JNIEnv* env = AttachCurrentThread();
ScopedJavaLocalRef<jstring> str = ConvertUTF8ToJavaString(env, "string");
ScopedJavaGlobalRef<jstring> global(str);
ScopedJavaGlobalRef<jobject> global_obj(str);
ScopedJavaLocalRef<jobject> local_obj(global);
const JavaRef<jobject>& obj_ref1(str);
const JavaRef<jobject>& obj_ref2(global);
EXPECT_TRUE(env->IsSameObject(obj_ref1.obj(), obj_ref2.obj()));
EXPECT_TRUE(env->IsSameObject(global_obj.obj(), obj_ref2.obj()));
const JavaRef<jstring>& str_ref = str;
EXPECT_EQ("string", ConvertJavaStringToUTF8(str_ref));
TEST_F(ScopedJavaRefTest, RefCounts) {
JNIEnv* env = AttachCurrentThread();
ScopedJavaLocalRef<jstring> str;
// The ConvertJavaStringToUTF8 below creates a new string that would normally
// return a local ref. We simulate that by starting the g_local_refs count at
// 1.
g_local_refs = 1;
str.Reset(ConvertUTF8ToJavaString(env, "string"));
EXPECT_EQ(1, g_local_refs);
EXPECT_EQ(0, g_global_refs);
ScopedJavaGlobalRef<jstring> global_str(str);
ScopedJavaGlobalRef<jobject> global_obj(global_str);
EXPECT_EQ(1, g_local_refs);
EXPECT_EQ(2, g_global_refs);
ScopedJavaLocalRef<jstring> str2(env, str.Release());
EXPECT_EQ(1, g_local_refs);
ScopedJavaLocalRef<jstring> str3(str2);
EXPECT_EQ(2, g_local_refs);
EXPECT_EQ(1, g_local_refs);
EXPECT_EQ(0, g_local_refs);
EXPECT_EQ(1, g_global_refs);
ScopedJavaGlobalRef<jobject> global_obj2(global_obj);
EXPECT_EQ(2, g_global_refs);
EXPECT_EQ(0, g_local_refs);
EXPECT_EQ(0, g_global_refs);
} // namespace android
} // namespace base