Refactor ScopedJavaRef

base/android/scoped_java_ref_unittest.cc

+// Copyright (c) 2011 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;
+
+jobject NewGlobalRef(JNIEnv* env, jobject obj) {
+  ++g_global_refs;
+  return AttachCurrentThread()->NewGlobalRef(obj);
+}
+
+void DeleteGlobalRef(JNIEnv* env, jobject obj) {
+  --g_global_refs;
+  return AttachCurrentThread()->DeleteGlobalRef(obj);
+}
+
+jobject NewLocalRef(JNIEnv* env, jobject obj) {
+  ++g_local_refs;
+  return AttachCurrentThread()->NewLocalRef(obj);
+}
+
+void DeleteLocalRef(JNIEnv* env, jobject obj) {
+  --g_local_refs;
+  return AttachCurrentThread()->DeleteLocalRef(obj);
+}
+}  // namespace
+
+class ScopedJavaRefTest : public testing::Test {
+ protected:
+  virtual void SetUp() {
+    g_local_refs = 0;
+    g_global_refs = 0;
+    JNIEnv* env = AttachCurrentThread();
+    counting_env = *env;
+    counting_functions = *counting_env.functions;
+    counting_functions.NewGlobalRef = &NewGlobalRef;
+    counting_functions.DeleteGlobalRef = &DeleteGlobalRef;
+    counting_functions.NewLocalRef = &NewLocalRef;
+    counting_functions.DeleteLocalRef = &DeleteLocalRef;
+    counting_env.functions = &counting_functions;
+  }
+
+  // Special JNI env configured in SetUp to count in and out all local & global
+  // reference instances. Be careful to only use this with the ScopedJavaRef
+  // classes under test, else it's easy to get system references counted in
+  // here too.
+  JNIEnv counting_env;
+  JNINativeInterface counting_functions;
+};
+
+// The main purpose of this is testing the various conversions compile.
+TEST_F(ScopedJavaRefTest, Conversions) {
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jstring> str(env, 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()));
+  }
+  global.Reset(str);
+  const JavaRef<jstring>& str_ref = str;
+  EXPECT_EQ("string", ConvertJavaStringToUTF8(env, str_ref.obj()));
+  str.Reset();
+}
+
+TEST_F(ScopedJavaRefTest, RefCounts) {
+  ScopedJavaLocalRef<jstring> str;
+  str.Reset(&counting_env, ConvertUTF8ToJavaString(AttachCurrentThread(),
+                                                   "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(&counting_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);
+    str2.Reset();
+    EXPECT_EQ(0, g_local_refs);
+    global_str.Reset();
+    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