Fixes JNI Bindings & startup perf.

This patch follows digit's suggestions:
- Removes ScopedJavaObject for jclasses.
- Uses const char kFoo[] rather than pointers.

BUG=
TEST=base/android/jni_generator/jni_generator_tests.py


Review URL: http://codereview.chromium.org/9466024

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@124413 0039d316-1c4b-4281-b951-d872f2087c98

base/android/jni_generator/golden_sample_for_tests_jni.h

@@ -22,18 +22,14 @@ using base::android::ScopedJavaLocalRef;
 
 // Step 1: forward declarations.
 namespace {
-const char* const kInnerClassClassPath =
+const char kInnerClassClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests$InnerClass";
-const char* const kSampleForTestsClassPath =
+const char kSampleForTestsClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests";
-// Leaking this JavaRef as we cannot use LazyInstance from some threads.
-base::android::ScopedJavaGlobalRef<jclass>&
-    g_InnerClass_clazz =
-        *(new base::android::ScopedJavaGlobalRef<jclass>());
-// Leaking this JavaRef as we cannot use LazyInstance from some threads.
-base::android::ScopedJavaGlobalRef<jclass>&
-    g_SampleForTests_clazz =
-        *(new base::android::ScopedJavaGlobalRef<jclass>());
+// Leaking this jclass as we cannot use LazyInstance from some threads.
+jclass g_InnerClass_clazz = NULL;
+// Leaking this jclass as we cannot use LazyInstance from some threads.
+jclass g_SampleForTests_clazz = NULL;
 }  // namespace
 
 static jint Init(JNIEnv* env, jobject obj);
@@ -90,7 +86,7 @@ static jmethodID g_SampleForTests_javaMethod = 0;
 static jint Java_SampleForTests_javaMethod(JNIEnv* env, jobject obj, jint foo,
     jint bar) {
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_SampleForTests_clazz.is_null());
+  DCHECK(g_SampleForTests_clazz);
   DCHECK(g_SampleForTests_javaMethod);
   jint ret =
     env->CallIntMethod(obj,
@@ -102,10 +98,10 @@ static jint Java_SampleForTests_javaMethod(JNIEnv* env, jobject obj, jint foo,
 static jmethodID g_SampleForTests_staticJavaMethod = 0;
 static jboolean Java_SampleForTests_staticJavaMethod(JNIEnv* env) {
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_SampleForTests_clazz.is_null());
+  DCHECK(g_SampleForTests_clazz);
   DCHECK(g_SampleForTests_staticJavaMethod);
   jboolean ret =
-    env->CallStaticBooleanMethod(g_SampleForTests_clazz.obj(),
+    env->CallStaticBooleanMethod(g_SampleForTests_clazz,
       g_SampleForTests_staticJavaMethod);
   base::android::CheckException(env);
   return ret;
@@ -115,7 +111,7 @@ static jmethodID g_SampleForTests_packagePrivateJavaMethod = 0;
 static void Java_SampleForTests_packagePrivateJavaMethod(JNIEnv* env, jobject
     obj) {
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_SampleForTests_clazz.is_null());
+  DCHECK(g_SampleForTests_clazz);
   DCHECK(g_SampleForTests_packagePrivateJavaMethod);
 
   env->CallVoidMethod(obj,
@@ -128,7 +124,7 @@ static jmethodID g_SampleForTests_methodThatThrowsException = 0;
 static void Java_SampleForTests_methodThatThrowsException(JNIEnv* env, jobject
     obj) {
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_SampleForTests_clazz.is_null());
+  DCHECK(g_SampleForTests_clazz);
   DCHECK(g_SampleForTests_methodThatThrowsException);
 
   env->CallVoidMethod(obj,
@@ -140,7 +136,7 @@ static void Java_SampleForTests_methodThatThrowsException(JNIEnv* env, jobject
 static jmethodID g_InnerClass_JavaInnerMethod = 0;
 static jfloat Java_InnerClass_JavaInnerMethod(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_InnerClass_clazz.is_null());
+  DCHECK(g_InnerClass_clazz);
   DCHECK(g_InnerClass_JavaInnerMethod);
   jfloat ret =
     env->CallFloatMethod(obj,
@@ -152,10 +148,10 @@ static jfloat Java_InnerClass_JavaInnerMethod(JNIEnv* env, jobject obj) {
 static jmethodID g_InnerClass_javaInnerFunction = 0;
 static void Java_InnerClass_javaInnerFunction(JNIEnv* env) {
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_InnerClass_clazz.is_null());
+  DCHECK(g_InnerClass_clazz);
   DCHECK(g_InnerClass_javaInnerFunction);
 
-  env->CallStaticVoidMethod(g_InnerClass_clazz.obj(),
+  env->CallStaticVoidMethod(g_InnerClass_clazz,
       g_InnerClass_javaInnerFunction);
   base::android::CheckException(env);
 
@@ -165,13 +161,14 @@ static void Java_InnerClass_javaInnerFunction(JNIEnv* env) {
 
 
 static void GetMethodIDsImpl(JNIEnv* env) {
-  g_InnerClass_clazz.Reset(
-      base::android::GetClass(env, kInnerClassClassPath));
-  g_SampleForTests_clazz.Reset(
-      base::android::GetClass(env, kSampleForTestsClassPath));
-  g_SampleForTests_javaMethod = base::android::GetMethodID(
-    env, g_SampleForTests_clazz,
-    "javaMethod",
+  g_InnerClass_clazz = reinterpret_cast<jclass>(env->NewGlobalRef(
+      base::android::GetUnscopedClass(env, kInnerClassClassPath)));
+  g_SampleForTests_clazz = reinterpret_cast<jclass>(env->NewGlobalRef(
+      base::android::GetUnscopedClass(env, kSampleForTestsClassPath)));
+  g_SampleForTests_javaMethod =
+      base::android::GetMethodID(
+          env, g_SampleForTests_clazz,
+          "javaMethod",
 
 "("
 "I"
@@ -179,41 +176,46 @@ static void GetMethodIDsImpl(JNIEnv* env) {
 ")"
 "I");
 
-  g_SampleForTests_staticJavaMethod = base::android::GetStaticMethodID(
-    env, g_SampleForTests_clazz,
-    "staticJavaMethod",
+  g_SampleForTests_staticJavaMethod =
+      base::android::GetStaticMethodID(
+          env, g_SampleForTests_clazz,
+          "staticJavaMethod",
 
 "("
 ")"
 "Z");
 
-  g_SampleForTests_packagePrivateJavaMethod = base::android::GetMethodID(
-    env, g_SampleForTests_clazz,
-    "packagePrivateJavaMethod",
+  g_SampleForTests_packagePrivateJavaMethod =
+      base::android::GetMethodID(
+          env, g_SampleForTests_clazz,
+          "packagePrivateJavaMethod",
 
 "("
 ")"
 "V");
 
-  g_SampleForTests_methodThatThrowsException = base::android::GetMethodID(
-    env, g_SampleForTests_clazz,
-    "methodThatThrowsException",
+  g_SampleForTests_methodThatThrowsException =
+      base::android::GetMethodID(
+          env, g_SampleForTests_clazz,
+          "methodThatThrowsException",
 
 "("
 ")"
 "V");
 
-  g_InnerClass_JavaInnerMethod = base::android::GetMethodID(
-    env, g_InnerClass_clazz,
-    "JavaInnerMethod",
+  g_InnerClass_JavaInnerMethod =
+      base::android::GetMethodID(
+          env, g_InnerClass_clazz,
+          "JavaInnerMethod",
 
 "("
 ")"
 "F");
 
-  g_InnerClass_javaInnerFunction = base::android::GetStaticMethodID(
-    env, g_InnerClass_clazz,
-    "javaInnerFunction",
+  g_InnerClass_javaInnerFunction =
+      base::android::GetStaticMethodID(
+          env, g_InnerClass_clazz,
+          "javaInnerFunction",
 
 "("
 ")"
@@ -237,7 +239,7 @@ static bool RegisterNativesImpl(JNIEnv* env) {
   };
   const int kMethodsInnerClassSize = arraysize(kMethodsInnerClass);
 
-  if (env->RegisterNatives(g_InnerClass_clazz.obj(),
+  if (env->RegisterNatives(g_InnerClass_clazz,
                            kMethodsInnerClass,
                            kMethodsInnerClassSize) < 0) {
     LOG(ERROR) << "RegisterNatives failed in " << __FILE__;
@@ -284,7 +286,7 @@ static bool RegisterNativesImpl(JNIEnv* env) {
   };
   const int kMethodsSampleForTestsSize = arraysize(kMethodsSampleForTests);
 
-  if (env->RegisterNatives(g_SampleForTests_clazz.obj(),
+  if (env->RegisterNatives(g_SampleForTests_clazz,
                            kMethodsSampleForTests,
                            kMethodsSampleForTestsSize) < 0) {
     LOG(ERROR) << "RegisterNatives failed in " << __FILE__;

base/android/jni_generator/jni_generator.py

@@ -605,7 +605,7 @@ ${KMETHODS}
   };
   const int kMethods${JAVA_CLASS}Size = arraysize(kMethods${JAVA_CLASS});
 
-  if (env->RegisterNatives(g_${JAVA_CLASS}_clazz.obj(),
+  if (env->RegisterNatives(g_${JAVA_CLASS}_clazz,
                            kMethods${JAVA_CLASS},
                            kMethods${JAVA_CLASS}Size) < 0) {
     LOG(ERROR) << "RegisterNatives failed in " << __FILE__;
@@ -724,7 +724,7 @@ ${FUNCTION_SIGNATURE} {""")
 static jmethodID g_${JAVA_CLASS}_${METHOD_ID_VAR_NAME} = 0;
 ${FUNCTION_HEADER}
   /* Must call RegisterNativesImpl()  */
-  DCHECK(!g_${JAVA_CLASS}_clazz.is_null());
+  DCHECK(g_${JAVA_CLASS}_clazz);
   DCHECK(g_${JAVA_CLASS}_${METHOD_ID_VAR_NAME});
   ${RETURN_DECLARATION}
   ${PRE_CALL}env->Call${STATIC}${ENV_CALL}Method(${FIRST_PARAM_IN_CALL},
@@ -734,7 +734,7 @@ ${FUNCTION_HEADER}
 }""")
     if called_by_native.static:
       first_param_in_declaration = ''
-      first_param_in_call = ('g_%s_clazz.obj()' %
+      first_param_in_call = ('g_%s_clazz' %
                              (called_by_native.java_class_name or
                               self.class_name))
     else:
@@ -816,7 +816,7 @@ ${FUNCTION_HEADER}
     """Returns the ClassPath constants."""
     ret = []
     template = Template("""\
-const char* const k${JAVA_CLASS}ClassPath = "${JNI_CLASS_PATH}";""")
+const char k${JAVA_CLASS}ClassPath[] = "${JNI_CLASS_PATH}";""")
     native_classes = self.GetUniqueClasses(self.natives)
     called_by_native_classes = self.GetUniqueClasses(self.called_by_natives)
     all_classes = native_classes
@@ -830,10 +830,8 @@ const char* const k${JAVA_CLASS}ClassPath = "${JNI_CLASS_PATH}";""")
     ret += ''
     for clazz in called_by_native_classes:
       template = Template("""\
-// Leaking this JavaRef as we cannot use LazyInstance from some threads.
-base::android::ScopedJavaGlobalRef<jclass>&
-    g_${JAVA_CLASS}_clazz =
-        *(new base::android::ScopedJavaGlobalRef<jclass>());""")
+// Leaking this jclass as we cannot use LazyInstance from some threads.
+jclass g_${JAVA_CLASS}_clazz = NULL;""")
       values = {
           'JAVA_CLASS': clazz,
       }
@@ -843,8 +841,8 @@ base::android::ScopedJavaGlobalRef<jclass>&
   def GetFindClasses(self):
     """Returns the imlementation of FindClass for all known classes."""
     template = Template("""\
-  g_${JAVA_CLASS}_clazz.Reset(
-      base::android::GetClass(env, k${JAVA_CLASS}ClassPath));""")
+  g_${JAVA_CLASS}_clazz = reinterpret_cast<jclass>(env->NewGlobalRef(
+      base::android::GetUnscopedClass(env, k${JAVA_CLASS}ClassPath)));""")
     ret = []
     for clazz in self.GetUniqueClasses(self.called_by_natives):
       values = {'JAVA_CLASS': clazz}
@@ -854,10 +852,11 @@ base::android::ScopedJavaGlobalRef<jclass>&
   def GetMethodIDImpl(self, called_by_native):
     """Returns the implementation of GetMethodID."""
     template = Template("""\
-  g_${JAVA_CLASS}_${METHOD_ID_VAR_NAME} = base::android::Get${STATIC}MethodID(
-    env, g_${JAVA_CLASS}_clazz,
-    "${NAME}",
-    ${JNI_SIGNATURE});
+  g_${JAVA_CLASS}_${METHOD_ID_VAR_NAME} =
+      base::android::Get${STATIC}MethodID(
+          env, g_${JAVA_CLASS}_clazz,
+          "${NAME}",
+          ${JNI_SIGNATURE});
 """)
     values = {
         'JAVA_CLASS': called_by_native.java_class_name or self.class_name,