Make class lookup lazy in jni_generator when using lazy method lookup.

This removes the eager class registration from RegisterNatives when possible.

BUG=402003
TBR=sievers@chromium.org, brettw@chromium.org

Review URL: https://codereview.chromium.org/472553002

Cr-Commit-Position: refs/heads/master@{#290810}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@290810 0039d316-1c4b-4281-b951-d872f2087c98

android_webview/lib/main/webview_entry_point.cc

@@ -6,6 +6,7 @@
 #include "android_webview/native/android_webview_jni_registrar.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_registrar.h"
+#include "base/android/jni_utils.h"
 #include "base/android/library_loader/library_loader_hooks.h"
 #include "components/navigation_interception/component_jni_registrar.h"
 #include "components/web_contents_delegate_android/component_jni_registrar.h"
@@ -47,6 +48,9 @@ JNI_EXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
   if (!android_webview::RegisterJni(env))
     return -1;
 
+  base::android::InitReplacementClassLoader(env,
+                                            base::android::GetClassLoader(env));
+
   content::SetContentMainDelegate(new android_webview::AwMainDelegate());
 
   // Initialize url lib here while we are still single-threaded, in case we use

base/BUILD.gn

@@ -49,6 +49,8 @@ component("base") {
     "android/jni_registrar.h",
     "android/jni_string.cc",
     "android/jni_string.h",
+    "android/jni_utils.cc",
+    "android/jni_utils.h",
     "android/jni_weak_ref.cc",
     "android/jni_weak_ref.h",
     "android/library_loader/library_loader_hooks.cc",
@@ -1343,6 +1345,7 @@ if (is_android) {
       "android/java/src/org/chromium/base/EventLog.java",
       "android/java/src/org/chromium/base/FieldTrialList.java",
       "android/java/src/org/chromium/base/ImportantFileWriterAndroid.java",
+      "android/java/src/org/chromium/base/JNIUtils.java",
       "android/java/src/org/chromium/base/library_loader/LibraryLoader.java",
       "android/java/src/org/chromium/base/MemoryPressureListener.java",
       "android/java/src/org/chromium/base/JavaHandlerThread.java",

base/android/base_jni_registrar.cc

@@ -15,6 +15,7 @@
 #include "base/android/java_handler_thread.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_registrar.h"
+#include "base/android/jni_utils.h"
 #include "base/android/memory_pressure_listener_android.h"
 #include "base/android/path_service_android.h"
 #include "base/android/path_utils.h"
@@ -40,6 +41,7 @@ static RegistrationMethod kBaseRegisteredMethods[] = {
   { "FieldTrialList", base::android::RegisterFieldTrialList },
   { "ImportantFileWriterAndroid",
     base::android::RegisterImportantFileWriterAndroid },
+  { "JNIUtils", base::android::RegisterJNIUtils },
   { "MemoryPressureListenerAndroid",
       base::android::MemoryPressureListenerAndroid::Register },
   { "JavaHandlerThread", base::android::JavaHandlerThread::RegisterBindings },

base/android/java/src/org/chromium/base/JNIUtils.java

+// Copyright 2014 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.
+
+package org.chromium.base;
+
+/**
+ * This class provides JNI-related methods to the native library.
+ */
+public class JNIUtils {
+    /**
+     * This returns a ClassLoader that is capable of loading Chromium Java code. Such a ClassLoader
+     * is needed for the few cases where the JNI mechanism is unable to automatically determine the
+     * appropriate ClassLoader instance.
+     */
+    @CalledByNative
+    public static Object getClassLoader() {
+        return JNIUtils.class.getClassLoader();
+    }
+}

base/android/jni_android.cc

@@ -8,6 +8,7 @@
 
 #include "base/android/build_info.h"
 #include "base/android/jni_string.h"
+#include "base/android/jni_utils.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 
@@ -21,6 +22,9 @@ JavaVM* g_jvm = NULL;
 // that may still be running at shutdown. There is no harm in doing this.
 base::LazyInstance<base::android::ScopedJavaGlobalRef<jobject> >::Leaky
     g_application_context = LAZY_INSTANCE_INITIALIZER;
+base::LazyInstance<base::android::ScopedJavaGlobalRef<jobject> >::Leaky
+    g_class_loader = LAZY_INSTANCE_INITIALIZER;
+jmethodID g_class_loader_load_class_method_id = 0;
 
 std::string GetJavaExceptionInfo(JNIEnv* env, jthrowable java_throwable) {
   ScopedJavaLocalRef<jclass> throwable_clazz =
@@ -118,17 +122,68 @@ void InitApplicationContext(JNIEnv* env, const JavaRef<jobject>& context) {
   g_application_context.Get().Reset(context);
 }
 
+void InitReplacementClassLoader(JNIEnv* env,
+                                const JavaRef<jobject>& class_loader) {
+  DCHECK(g_class_loader.Get().is_null());
+  DCHECK(!class_loader.is_null());
+
+  ScopedJavaLocalRef<jclass> class_loader_clazz =
+      GetClass(env, "java/lang/ClassLoader");
+  CHECK(!ClearException(env));
+  g_class_loader_load_class_method_id =
+      env->GetMethodID(class_loader_clazz.obj(),
+                       "loadClass",
+                       "(Ljava/lang/String;)Ljava/lang/Class;");
+  CHECK(!ClearException(env));
+
+  DCHECK(env->IsInstanceOf(class_loader.obj(), class_loader_clazz.obj()));
+  g_class_loader.Get().Reset(class_loader);
+}
+
 const jobject GetApplicationContext() {
   DCHECK(!g_application_context.Get().is_null());
   return g_application_context.Get().obj();
 }
 
 ScopedJavaLocalRef<jclass> GetClass(JNIEnv* env, const char* class_name) {
-  jclass clazz = env->FindClass(class_name);
+  jclass clazz;
+  if (!g_class_loader.Get().is_null()) {
+    clazz = static_cast<jclass>(
+        env->CallObjectMethod(g_class_loader.Get().obj(),
+                              g_class_loader_load_class_method_id,
+                              ConvertUTF8ToJavaString(env, class_name).obj()));
+  } else {
+    clazz = env->FindClass(class_name);
+  }
   CHECK(!ClearException(env) && clazz) << "Failed to find class " << class_name;
   return ScopedJavaLocalRef<jclass>(env, clazz);
 }
 
+jclass LazyGetClass(
+    JNIEnv* env,
+    const char* class_name,
+    base::subtle::AtomicWord* atomic_class_id) {
+  COMPILE_ASSERT(sizeof(subtle::AtomicWord) >= sizeof(jclass),
+                 AtomicWord_SmallerThan_jMethodID);
+  subtle::AtomicWord value = base::subtle::Acquire_Load(atomic_class_id);
+  if (value)
+    return reinterpret_cast<jclass>(value);
+  ScopedJavaGlobalRef<jclass> clazz;
+  clazz.Reset(GetClass(env, class_name));
+  subtle::AtomicWord null_aw = reinterpret_cast<subtle::AtomicWord>(NULL);
+  subtle::AtomicWord cas_result = base::subtle::Release_CompareAndSwap(
+      atomic_class_id,
+      null_aw,
+      reinterpret_cast<subtle::AtomicWord>(clazz.obj()));
+  if (cas_result == null_aw) {
+    // We intentionally leak the global ref since we now storing it as a raw
+    // pointer in |atomic_class_id|.
+    return clazz.Release();
+  } else {
+    return reinterpret_cast<jclass>(cas_result);
+  }
+}
+
 template<MethodID::Type type>
 jmethodID MethodID::Get(JNIEnv* env,
                         jclass clazz,

base/android/jni_android.h

@@ -53,6 +53,15 @@ BASE_EXPORT bool IsVMInitialized();
 BASE_EXPORT void InitApplicationContext(JNIEnv* env,
                                         const JavaRef<jobject>& context);
 
+// Initializes the global ClassLoader used by the GetClass and LazyGetClass
+// methods. This is needed because JNI will use the base ClassLoader when there
+// is no Java code on the stack. The base ClassLoader doesn't know about any of
+// the application classes and will fail to lookup anything other than system
+// classes.
+BASE_EXPORT void InitReplacementClassLoader(
+    JNIEnv* env,
+    const JavaRef<jobject>& class_loader);
+
 // Gets a global ref to the application context set with
 // InitApplicationContext(). Ownership is retained by the function - the caller
 // must NOT release it.
@@ -66,6 +75,17 @@ const BASE_EXPORT jobject GetApplicationContext();
 BASE_EXPORT ScopedJavaLocalRef<jclass> GetClass(JNIEnv* env,
                                                 const char* class_name);
 
+// The method will initialize |atomic_class_id| to contain a global ref to the
+// class. And will return that ref on subsequent calls.  It's the caller's
+// responsibility to release the ref when it is no longer needed.
+// The caller is responsible to zero-initialize |atomic_method_id|.
+// It's fine to simultaneously call this on multiple threads referencing the
+// same |atomic_method_id|.
+BASE_EXPORT jclass LazyGetClass(
+    JNIEnv* env,
+    const char* class_name,
+    base::subtle::AtomicWord* atomic_class_id);
+
 // This class is a wrapper for JNIEnv Get(Static)MethodID.
 class BASE_EXPORT MethodID {
  public:

base/android/jni_generator/golden_sample_for_tests_jni.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -24,12 +24,22 @@ const char kSampleForTestsClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests";
 const char kInnerStructBClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests$InnerStructB";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_InnerStructA_clazz = NULL;
+jclass InnerStructA_clazz(JNIEnv*) { return g_InnerStructA_clazz; }
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_SampleForTests_clazz = NULL;
+jclass SampleForTests_clazz(JNIEnv*) { return g_SampleForTests_clazz; }
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_InnerStructB_clazz = NULL;
+jclass InnerStructB_clazz(JNIEnv*) { return g_InnerStructB_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -99,11 +109,11 @@ static jint Java_SampleForTests_javaMethod(JNIEnv* env, jobject obj,
     JniIntWrapper bar) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz, 0);
+      SampleForTests_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "javaMethod",
 
 "("
@@ -123,12 +133,12 @@ static jint Java_SampleForTests_javaMethod(JNIEnv* env, jobject obj,
 static base::subtle::AtomicWord g_SampleForTests_staticJavaMethod = 0;
 static jboolean Java_SampleForTests_staticJavaMethod(JNIEnv* env) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_SampleForTests_clazz,
-      g_SampleForTests_clazz, false);
+  CHECK_CLAZZ(env, SampleForTests_clazz(env),
+      SampleForTests_clazz(env), false);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "staticJavaMethod",
 
 "("
@@ -137,7 +147,7 @@ static jboolean Java_SampleForTests_staticJavaMethod(JNIEnv* env) {
       &g_SampleForTests_staticJavaMethod);
 
   jboolean ret =
-      env->CallStaticBooleanMethod(g_SampleForTests_clazz,
+      env->CallStaticBooleanMethod(SampleForTests_clazz(env),
           method_id);
   jni_generator::CheckException(env);
   return ret;
@@ -148,11 +158,11 @@ static void Java_SampleForTests_packagePrivateJavaMethod(JNIEnv* env, jobject
     obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz);
+      SampleForTests_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "packagePrivateJavaMethod",
 
 "("
@@ -171,11 +181,11 @@ static void Java_SampleForTests_methodThatThrowsException(JNIEnv* env, jobject
     obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz);
+      SampleForTests_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "methodThatThrowsException",
 
 "("
@@ -194,12 +204,12 @@ static base::android::ScopedJavaLocalRef<jobject>
     JniIntWrapper i,
     jstring s) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_InnerStructA_clazz,
-      g_InnerStructA_clazz, NULL);
+  CHECK_CLAZZ(env, InnerStructA_clazz(env),
+      InnerStructA_clazz(env), NULL);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_InnerStructA_clazz,
+      env, InnerStructA_clazz(env),
       "create",
 
 "("
@@ -211,7 +221,7 @@ static base::android::ScopedJavaLocalRef<jobject>
       &g_InnerStructA_create);
 
   jobject ret =
-      env->CallStaticObjectMethod(g_InnerStructA_clazz,
+      env->CallStaticObjectMethod(InnerStructA_clazz(env),
           method_id, l, as_jint(i), s);
   jni_generator::CheckException(env);
   return base::android::ScopedJavaLocalRef<jobject>(env, ret);
@@ -222,11 +232,11 @@ static void Java_SampleForTests_addStructA(JNIEnv* env, jobject obj, jobject a)
     {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz);
+      SampleForTests_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "addStructA",
 
 "("
@@ -246,11 +256,11 @@ static void Java_SampleForTests_iterateAndDoSomething(JNIEnv* env, jobject obj)
     {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz);
+      SampleForTests_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "iterateAndDoSomething",
 
 "("
@@ -268,11 +278,11 @@ static base::subtle::AtomicWord g_InnerStructB_getKey = 0;
 static jlong Java_InnerStructB_getKey(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InnerStructB_clazz, 0);
+      InnerStructB_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InnerStructB_clazz,
+      env, InnerStructB_clazz(env),
       "getKey",
 
 "("
@@ -292,11 +302,11 @@ static base::android::ScopedJavaLocalRef<jstring>
     Java_InnerStructB_getValue(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InnerStructB_clazz, NULL);
+      InnerStructB_clazz(env), NULL);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InnerStructB_clazz,
+      env, InnerStructB_clazz(env),
       "getValue",
 
 "("
@@ -379,11 +389,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsSampleForTestsSize = arraysize(kMethodsSampleForTests);
 
-  if (env->RegisterNatives(g_SampleForTests_clazz,
+  if (env->RegisterNatives(SampleForTests_clazz(env),
                            kMethodsSampleForTests,
                            kMethodsSampleForTestsSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_SampleForTests_clazz, __FILE__);
+        env, SampleForTests_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/jni_generator.py

@@ -731,7 +731,7 @@ class InlHeaderFileGenerator(object):
   def GetContent(self):
     """Returns the content of the JNI binding file."""
     template = Template("""\
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -947,11 +947,11 @@ ${CALLED_BY_NATIVES}
     template = Template("""\
   const int kMethods${JAVA_CLASS}Size = arraysize(kMethods${JAVA_CLASS});
 
-  if (env->RegisterNatives(g_${JAVA_CLASS}_clazz,
+  if (env->RegisterNatives(${JAVA_CLASS}_clazz(env),
                            kMethods${JAVA_CLASS},
                            kMethods${JAVA_CLASS}Size) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_${JAVA_CLASS}_clazz, __FILE__);
+        env, ${JAVA_CLASS}_clazz(env), __FILE__);
     return false;
   }
 """)
@@ -1122,11 +1122,10 @@ static ${RETURN} ${NAME}(JNIEnv* env, ${PARAMS_IN_DECLARATION}) {"""
 
   def GetCalledByNativeValues(self, called_by_native):
     """Fills in necessary values for the CalledByNative methods."""
+    java_class = called_by_native.java_class_name or self.class_name
     if called_by_native.static or called_by_native.is_constructor:
       first_param_in_declaration = ''
-      first_param_in_call = ('g_%s_clazz' %
-                             (called_by_native.java_class_name or
-                              self.class_name))
+      first_param_in_call = ('%s_clazz(env)' % java_class)
     else:
       first_param_in_declaration = ', jobject obj'
       first_param_in_call = 'obj'
@@ -1160,7 +1159,7 @@ static ${RETURN} ${NAME}(JNIEnv* env, ${PARAMS_IN_DECLARATION}) {"""
       else:
         return_clause = 'return ret;'
     return {
-        'JAVA_CLASS': called_by_native.java_class_name or self.class_name,
+        'JAVA_CLASS': java_class,
         'RETURN_TYPE': return_type,
         'OPTIONAL_ERROR_RETURN': optional_error_return,
         'RETURN_DECLARATION': return_declaration,
@@ -1204,7 +1203,7 @@ static base::subtle::AtomicWord g_${JAVA_CLASS}_${METHOD_ID_VAR_NAME} = 0;
 ${FUNCTION_HEADER}
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, ${FIRST_PARAM_IN_CALL},
-      g_${JAVA_CLASS}_clazz${OPTIONAL_ERROR_RETURN});
+      ${JAVA_CLASS}_clazz(env)${OPTIONAL_ERROR_RETURN});
   jmethodID method_id =
     ${GET_METHOD_ID_IMPL}
   ${RETURN_DECLARATION}
@@ -1263,22 +1262,56 @@ const char k${JAVA_CLASS}ClassPath[] = "${JNI_CLASS_PATH}";""")
       }
       ret += [template.substitute(values)]
     ret += ''
-    for clazz in called_by_native_classes:
+
+    class_getter_methods = []
+    if self.options.native_exports:
       template = Template("""\
 // Leaking this jclass as we cannot use LazyInstance from some threads.
-jclass g_${JAVA_CLASS}_clazz = NULL;""")
+base::subtle::AtomicWord g_${JAVA_CLASS}_clazz = 0;
+jclass ${JAVA_CLASS}_clazz(JNIEnv* env) {
+  return base::android::LazyGetClass(env, k${JAVA_CLASS}ClassPath, \
+    &g_${JAVA_CLASS}_clazz);
+}""")
+    else:
+      template = Template("""\
+// Leaking this jclass as we cannot use LazyInstance from some threads.
+jclass g_${JAVA_CLASS}_clazz = NULL;
+jclass ${JAVA_CLASS}_clazz(JNIEnv*) { return g_${JAVA_CLASS}_clazz; }""")
+
+    for clazz in called_by_native_classes:
       values = {
           'JAVA_CLASS': clazz,
       }
-      ret += [template.substitute(values)]
+      class_getter_methods += [template.substitute(values)]
+
+    template = Template("""\
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
+${CLASS_GETER_METHODS}
+#if __clang__
+#pragma clang diagnostic pop
+#endif""")
+    values = {
+      'CLASS_GETER_METHODS': '\n'.join(class_getter_methods)
+    }
+    ret += [template.substitute(values)]
     return '\n'.join(ret)
 
   def GetFindClasses(self):
     """Returns the imlementation of FindClass for all known classes."""
     if self.init_native:
-      template = Template("""\
+      if self.options.native_exports:
+        template = Template("""\
+    base::subtle::Release_Store(&g_${JAVA_CLASS}_clazz,
+      static_cast<base::subtle::AtomicWord>(env->NewWeakGlobalRef(clazz));""")
+      else:
+        template = Template("""\
   g_${JAVA_CLASS}_clazz = static_cast<jclass>(env->NewWeakGlobalRef(clazz));""")
     else:
+      if self.options.native_exports:
+        return '\n'
       template = Template("""\
   g_${JAVA_CLASS}_clazz = reinterpret_cast<jclass>(env->NewGlobalRef(
       base::android::GetClass(env, k${JAVA_CLASS}ClassPath).obj()));""")
@@ -1293,13 +1326,13 @@ jclass g_${JAVA_CLASS}_clazz = NULL;""")
     if self.options.eager_called_by_natives:
       template = Template("""\
 env->Get${STATIC_METHOD_PART}MethodID(
-      g_${JAVA_CLASS}_clazz,
+      ${JAVA_CLASS}_clazz(env),
       "${JNI_NAME}", ${JNI_SIGNATURE});""")
     else:
       template = Template("""\
   base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_${STATIC}>(
-      env, g_${JAVA_CLASS}_clazz,
+      env, ${JAVA_CLASS}_clazz(env),
       "${JNI_NAME}",
       ${JNI_SIGNATURE},
       &g_${JAVA_CLASS}_${METHOD_ID_VAR_NAME});

base/android/jni_generator/testEagerCalledByNativesOption.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kTestClassPath[] = "org/chromium/example/jni_generator/Test";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Test_clazz = NULL;
+jclass Test_clazz(JNIEnv*) { return g_Test_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 jmethodID g_Test_testMethodWithParam = NULL;
 jmethodID g_Test_testStaticMethodWithParam = NULL;
 jmethodID g_Test_testMethodWithNoParam = NULL;
@@ -46,20 +54,21 @@ static void testMethodWithParam(JNIEnv* env, jobject obj, JniIntWrapper iParam)
 }
 
 static jint testStaticMethodWithParam(JNIEnv* env, JniIntWrapper iParam) {
-  jint ret = env->CallStaticIntMethod(g_Test_clazz,
+  jint ret = env->CallStaticIntMethod(Test_clazz(env),
       g_Test_testStaticMethodWithParam, as_jint(iParam));
   return ret;
 }
 
 static jdouble testMethodWithNoParam(JNIEnv* env) {
-  jdouble ret = env->CallStaticDoubleMethod(g_Test_clazz,
+  jdouble ret = env->CallStaticDoubleMethod(Test_clazz(env),
       g_Test_testMethodWithNoParam);
   return ret;
 }
 
 static base::android::ScopedJavaLocalRef<jstring>
     testStaticMethodWithNoParam(JNIEnv* env) {
-  jstring ret = static_cast<jstring>(env->CallStaticObjectMethod(g_Test_clazz,
+  jstring ret =
+      static_cast<jstring>(env->CallStaticObjectMethod(Test_clazz(env),
       g_Test_testStaticMethodWithNoParam));
   return base::android::ScopedJavaLocalRef<jstring>(env, ret);
 }
@@ -81,16 +90,16 @@ static bool RegisterNativesImpl(JNIEnv* env, jclass clazz) {
 
   const int kMethodsTestSize = arraysize(kMethodsTest);
 
-  if (env->RegisterNatives(g_Test_clazz,
+  if (env->RegisterNatives(Test_clazz(env),
                            kMethodsTest,
                            kMethodsTestSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Test_clazz, __FILE__);
+        env, Test_clazz(env), __FILE__);
     return false;
   }
 
   g_Test_testMethodWithParam = env->GetMethodID(
-      g_Test_clazz,
+      Test_clazz(env),
       "testMethodWithParam",
 "("
 "I"
@@ -101,7 +110,7 @@ static bool RegisterNativesImpl(JNIEnv* env, jclass clazz) {
   }
 
   g_Test_testStaticMethodWithParam = env->GetStaticMethodID(
-      g_Test_clazz,
+      Test_clazz(env),
       "testStaticMethodWithParam",
 "("
 "I"
@@ -112,7 +121,7 @@ static bool RegisterNativesImpl(JNIEnv* env, jclass clazz) {
   }
 
   g_Test_testMethodWithNoParam = env->GetStaticMethodID(
-      g_Test_clazz,
+      Test_clazz(env),
       "testMethodWithNoParam",
 "("
 ")"
@@ -122,7 +131,7 @@ static bool RegisterNativesImpl(JNIEnv* env, jclass clazz) {
   }
 
   g_Test_testStaticMethodWithNoParam = env->GetStaticMethodID(
-      g_Test_clazz,
+      Test_clazz(env),
       "testStaticMethodWithNoParam",
 "("
 ")"

base/android/jni_generator/testFromJavaP.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kInputStreamClassPath[] = "java/io/InputStream";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_InputStream_clazz = NULL;
+jclass InputStream_clazz(JNIEnv*) { return g_InputStream_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -34,11 +42,11 @@ static jint Java_InputStream_available(JNIEnv* env, jobject obj) __attribute__
 static jint Java_InputStream_available(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz, 0);
+      InputStream_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "available",
       "()I",
       &g_InputStream_available);
@@ -56,11 +64,11 @@ static void Java_InputStream_close(JNIEnv* env, jobject obj) __attribute__
 static void Java_InputStream_close(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz);
+      InputStream_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "close",
       "()V",
       &g_InputStream_close);
@@ -77,11 +85,11 @@ static void Java_InputStream_mark(JNIEnv* env, jobject obj, JniIntWrapper p0)
 static void Java_InputStream_mark(JNIEnv* env, jobject obj, JniIntWrapper p0) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz);
+      InputStream_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "mark",
       "(I)V",
       &g_InputStream_mark);
@@ -98,11 +106,11 @@ static jboolean Java_InputStream_markSupported(JNIEnv* env, jobject obj)
 static jboolean Java_InputStream_markSupported(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz, false);
+      InputStream_clazz(env), false);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "markSupported",
       "()Z",
       &g_InputStream_markSupported);
@@ -120,11 +128,11 @@ static jint Java_InputStream_readI(JNIEnv* env, jobject obj) __attribute__
 static jint Java_InputStream_readI(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz, 0);
+      InputStream_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "read",
       "()I",
       &g_InputStream_readI);
@@ -142,11 +150,11 @@ static jint Java_InputStream_readI_AB(JNIEnv* env, jobject obj, jbyteArray p0)
 static jint Java_InputStream_readI_AB(JNIEnv* env, jobject obj, jbyteArray p0) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz, 0);
+      InputStream_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "read",
       "([B)I",
       &g_InputStream_readI_AB);
@@ -169,11 +177,11 @@ static jint Java_InputStream_readI_AB_I_I(JNIEnv* env, jobject obj, jbyteArray
     JniIntWrapper p2) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz, 0);
+      InputStream_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "read",
       "([BII)I",
       &g_InputStream_readI_AB_I_I);
@@ -191,11 +199,11 @@ static void Java_InputStream_reset(JNIEnv* env, jobject obj) __attribute__
 static void Java_InputStream_reset(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz);
+      InputStream_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "reset",
       "()V",
       &g_InputStream_reset);
@@ -212,11 +220,11 @@ static jlong Java_InputStream_skip(JNIEnv* env, jobject obj, jlong p0)
 static jlong Java_InputStream_skip(JNIEnv* env, jobject obj, jlong p0) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_InputStream_clazz, 0);
+      InputStream_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "skip",
       "(J)J",
       &g_InputStream_skip);
@@ -234,18 +242,18 @@ static base::android::ScopedJavaLocalRef<jobject>
 static base::android::ScopedJavaLocalRef<jobject>
     Java_InputStream_Constructor(JNIEnv* env) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_InputStream_clazz,
-      g_InputStream_clazz, NULL);
+  CHECK_CLAZZ(env, InputStream_clazz(env),
+      InputStream_clazz(env), NULL);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_InputStream_clazz,
+      env, InputStream_clazz(env),
       "<init>",
       "()V",
       &g_InputStream_Constructor);
 
   jobject ret =
-      env->NewObject(g_InputStream_clazz,
+      env->NewObject(InputStream_clazz(env),
           method_id);
   jni_generator::CheckException(env);
   return base::android::ScopedJavaLocalRef<jobject>(env, ret);

base/android/jni_generator/testFromJavaPGenerics.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kHashSetClassPath[] = "java/util/HashSet";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_HashSet_clazz = NULL;
+jclass HashSet_clazz(JNIEnv*) { return g_HashSet_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -34,11 +42,11 @@ static void Java_HashSet_dummy(JNIEnv* env, jobject obj) __attribute__
 static void Java_HashSet_dummy(JNIEnv* env, jobject obj) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_HashSet_clazz);
+      HashSet_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_HashSet_clazz,
+      env, HashSet_clazz(env),
       "dummy",
       "()V",
       &g_HashSet_dummy);

base/android/jni_generator/testInnerClassNatives.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -20,8 +20,16 @@
 namespace {
 const char kTestJniClassPath[] = "org/chromium/TestJni";
 const char kMyInnerClassClassPath[] = "org/chromium/TestJni$MyInnerClass";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_TestJni_clazz = NULL;
+jclass TestJni_clazz(JNIEnv*) { return g_TestJni_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -44,11 +52,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsMyInnerClassSize = arraysize(kMethodsMyInnerClass);
 
-  if (env->RegisterNatives(g_MyInnerClass_clazz,
+  if (env->RegisterNatives(MyInnerClass_clazz(env),
                            kMethodsMyInnerClass,
                            kMethodsMyInnerClassSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_MyInnerClass_clazz, __FILE__);
+        env, MyInnerClass_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testInnerClassNativesBothInnerAndOuter.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -21,8 +21,16 @@ namespace {
 const char kMyOtherInnerClassClassPath[] =
     "org/chromium/TestJni$MyOtherInnerClass";
 const char kTestJniClassPath[] = "org/chromium/TestJni";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_TestJni_clazz = NULL;
+jclass TestJni_clazz(JNIEnv*) { return g_TestJni_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -55,21 +63,21 @@ static bool RegisterNativesImpl(JNIEnv* env) {
   const int kMethodsMyOtherInnerClassSize =
       arraysize(kMethodsMyOtherInnerClass);
 
-  if (env->RegisterNatives(g_MyOtherInnerClass_clazz,
+  if (env->RegisterNatives(MyOtherInnerClass_clazz(env),
                            kMethodsMyOtherInnerClass,
                            kMethodsMyOtherInnerClassSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_MyOtherInnerClass_clazz, __FILE__);
+        env, MyOtherInnerClass_clazz(env), __FILE__);
     return false;
   }
 
   const int kMethodsTestJniSize = arraysize(kMethodsTestJni);
 
-  if (env->RegisterNatives(g_TestJni_clazz,
+  if (env->RegisterNatives(TestJni_clazz(env),
                            kMethodsTestJni,
                            kMethodsTestJniSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_TestJni_clazz, __FILE__);
+        env, TestJni_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testInnerClassNativesMultiple.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -22,8 +22,16 @@ const char kMyOtherInnerClassClassPath[] =
     "org/chromium/TestJni$MyOtherInnerClass";
 const char kTestJniClassPath[] = "org/chromium/TestJni";
 const char kMyInnerClassClassPath[] = "org/chromium/TestJni$MyInnerClass";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_TestJni_clazz = NULL;
+jclass TestJni_clazz(JNIEnv*) { return g_TestJni_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -56,21 +64,21 @@ static bool RegisterNativesImpl(JNIEnv* env) {
   const int kMethodsMyOtherInnerClassSize =
       arraysize(kMethodsMyOtherInnerClass);
 
-  if (env->RegisterNatives(g_MyOtherInnerClass_clazz,
+  if (env->RegisterNatives(MyOtherInnerClass_clazz(env),
                            kMethodsMyOtherInnerClass,
                            kMethodsMyOtherInnerClassSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_MyOtherInnerClass_clazz, __FILE__);
+        env, MyOtherInnerClass_clazz(env), __FILE__);
     return false;
   }
 
   const int kMethodsMyInnerClassSize = arraysize(kMethodsMyInnerClass);
 
-  if (env->RegisterNatives(g_MyInnerClass_clazz,
+  if (env->RegisterNatives(MyInnerClass_clazz(env),
                            kMethodsMyInnerClass,
                            kMethodsMyInnerClassSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_MyInnerClass_clazz, __FILE__);
+        env, MyInnerClass_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testJNIInitNativeNameOption.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kTestClassPath[] = "org/chromium/example/jni_generator/Test";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Test_clazz = NULL;
+jclass Test_clazz(JNIEnv*) { return g_Test_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -49,11 +57,11 @@ static bool RegisterNativesImpl(JNIEnv* env, jclass clazz) {
 
   const int kMethodsTestSize = arraysize(kMethodsTest);
 
-  if (env->RegisterNatives(g_Test_clazz,
+  if (env->RegisterNatives(Test_clazz(env),
                            kMethodsTest,
                            kMethodsTestSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Test_clazz, __FILE__);
+        env, Test_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testJarJarRemapping.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kExampleClassPath[] = "com/test/jni_generator/Example";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Example_clazz = NULL;
+jclass Example_clazz(JNIEnv*) { return g_Example_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -69,11 +77,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsExampleSize = arraysize(kMethodsExample);
 
-  if (env->RegisterNatives(g_Example_clazz,
+  if (env->RegisterNatives(Example_clazz(env),
                            kMethodsExample,
                            kMethodsExampleSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Example_clazz, __FILE__);
+        env, Example_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testMultipleJNIAdditionalImport.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kFooClassPath[] = "org/chromium/foo/Foo";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Foo_clazz = NULL;
+jclass Foo_clazz(JNIEnv*) { return g_Foo_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -34,12 +42,12 @@ static base::subtle::AtomicWord g_Foo_calledByNative = 0;
 static void Java_Foo_calledByNative(JNIEnv* env, jobject callback1,
     jobject callback2) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_Foo_clazz,
-      g_Foo_clazz);
+  CHECK_CLAZZ(env, Foo_clazz(env),
+      Foo_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_Foo_clazz,
+      env, Foo_clazz(env),
       "calledByNative",
 
 "("
@@ -49,7 +57,7 @@ static void Java_Foo_calledByNative(JNIEnv* env, jobject callback1,
 "V",
       &g_Foo_calledByNative);
 
-     env->CallStaticVoidMethod(g_Foo_clazz,
+     env->CallStaticVoidMethod(Foo_clazz(env),
           method_id, callback1, callback2);
   jni_generator::CheckException(env);
 
@@ -72,11 +80,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsFooSize = arraysize(kMethodsFoo);
 
-  if (env->RegisterNatives(g_Foo_clazz,
+  if (env->RegisterNatives(Foo_clazz(env),
                            kMethodsFoo,
                            kMethodsFooSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Foo_clazz, __FILE__);
+        env, Foo_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testNativeExportsOption.golden

@@ -20,8 +20,19 @@
 namespace {
 const char kSampleForTestsClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
-jclass g_SampleForTests_clazz = NULL;
+base::subtle::AtomicWord g_SampleForTests_clazz = 0;
+jclass SampleForTests_clazz(JNIEnv* env) {
+  return base::android::LazyGetClass(env, kSampleForTestsClassPath,
+      &g_SampleForTests_clazz);
+}
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -79,11 +90,11 @@ static void Java_SampleForTests_testMethodWithParam(JNIEnv* env, jobject obj,
     JniIntWrapper iParam) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz);
+      SampleForTests_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "testMethodWithParam",
 
 "("
@@ -105,11 +116,11 @@ static base::android::ScopedJavaLocalRef<jstring>
     JniIntWrapper iParam) {
   /* Must call RegisterNativesImpl()  */
   CHECK_CLAZZ(env, obj,
-      g_SampleForTests_clazz, NULL);
+      SampleForTests_clazz(env), NULL);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_INSTANCE>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "testMethodWithParamAndReturn",
 
 "("
@@ -129,12 +140,12 @@ static base::subtle::AtomicWord g_SampleForTests_testStaticMethodWithParam = 0;
 static jint Java_SampleForTests_testStaticMethodWithParam(JNIEnv* env,
     JniIntWrapper iParam) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_SampleForTests_clazz,
-      g_SampleForTests_clazz, 0);
+  CHECK_CLAZZ(env, SampleForTests_clazz(env),
+      SampleForTests_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "testStaticMethodWithParam",
 
 "("
@@ -144,7 +155,7 @@ static jint Java_SampleForTests_testStaticMethodWithParam(JNIEnv* env,
       &g_SampleForTests_testStaticMethodWithParam);
 
   jint ret =
-      env->CallStaticIntMethod(g_SampleForTests_clazz,
+      env->CallStaticIntMethod(SampleForTests_clazz(env),
           method_id, as_jint(iParam));
   jni_generator::CheckException(env);
   return ret;
@@ -153,12 +164,12 @@ static jint Java_SampleForTests_testStaticMethodWithParam(JNIEnv* env,
 static base::subtle::AtomicWord g_SampleForTests_testMethodWithNoParam = 0;
 static jdouble Java_SampleForTests_testMethodWithNoParam(JNIEnv* env) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_SampleForTests_clazz,
-      g_SampleForTests_clazz, 0);
+  CHECK_CLAZZ(env, SampleForTests_clazz(env),
+      SampleForTests_clazz(env), 0);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "testMethodWithNoParam",
 
 "("
@@ -167,7 +178,7 @@ static jdouble Java_SampleForTests_testMethodWithNoParam(JNIEnv* env) {
       &g_SampleForTests_testMethodWithNoParam);
 
   jdouble ret =
-      env->CallStaticDoubleMethod(g_SampleForTests_clazz,
+      env->CallStaticDoubleMethod(SampleForTests_clazz(env),
           method_id);
   jni_generator::CheckException(env);
   return ret;
@@ -178,12 +189,12 @@ static base::subtle::AtomicWord g_SampleForTests_testStaticMethodWithNoParam =
 static base::android::ScopedJavaLocalRef<jstring>
     Java_SampleForTests_testStaticMethodWithNoParam(JNIEnv* env) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_SampleForTests_clazz,
-      g_SampleForTests_clazz, NULL);
+  CHECK_CLAZZ(env, SampleForTests_clazz(env),
+      SampleForTests_clazz(env), NULL);
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_SampleForTests_clazz,
+      env, SampleForTests_clazz(env),
       "testStaticMethodWithNoParam",
 
 "("
@@ -192,7 +203,7 @@ static base::android::ScopedJavaLocalRef<jstring>
       &g_SampleForTests_testStaticMethodWithNoParam);
 
   jstring ret =
-      static_cast<jstring>(env->CallStaticObjectMethod(g_SampleForTests_clazz,
+static_cast<jstring>(env->CallStaticObjectMethod(SampleForTests_clazz(env),
           method_id));
   jni_generator::CheckException(env);
   return base::android::ScopedJavaLocalRef<jstring>(env, ret);
@@ -202,7 +213,8 @@ static base::android::ScopedJavaLocalRef<jstring>
 // Step 3: RegisterNatives.
 
 static bool RegisterNativesImpl(JNIEnv* env, jclass clazz) {
-  g_SampleForTests_clazz = static_cast<jclass>(env->NewWeakGlobalRef(clazz));
+    base::subtle::Release_Store(&g_SampleForTests_clazz,
+      static_cast<base::subtle::AtomicWord>(env->NewWeakGlobalRef(clazz));
 
   return true;
 }

base/android/jni_generator/testNatives.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kTestJniClassPath[] = "org/chromium/TestJni";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_TestJni_clazz = NULL;
+jclass TestJni_clazz(JNIEnv*) { return g_TestJni_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -202,11 +210,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsTestJniSize = arraysize(kMethodsTestJni);
 
-  if (env->RegisterNatives(g_TestJni_clazz,
+  if (env->RegisterNatives(TestJni_clazz(env),
                            kMethodsTestJni,
                            kMethodsTestJniSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_TestJni_clazz, __FILE__);
+        env, TestJni_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testNativesLong.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kTestJniClassPath[] = "org/chromium/TestJni";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_TestJni_clazz = NULL;
+jclass TestJni_clazz(JNIEnv*) { return g_TestJni_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -49,11 +57,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsTestJniSize = arraysize(kMethodsTestJni);
 
-  if (env->RegisterNatives(g_TestJni_clazz,
+  if (env->RegisterNatives(TestJni_clazz(env),
                            kMethodsTestJni,
                            kMethodsTestJniSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_TestJni_clazz, __FILE__);
+        env, TestJni_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testPureNativeMethodsOption.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kTestClassPath[] = "org/chromium/example/jni_generator/Test";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Test_clazz = NULL;
+jclass Test_clazz(JNIEnv*) { return g_Test_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -50,11 +58,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsTestSize = arraysize(kMethodsTest);
 
-  if (env->RegisterNatives(g_Test_clazz,
+  if (env->RegisterNatives(Test_clazz(env),
                            kMethodsTest,
                            kMethodsTestSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Test_clazz, __FILE__);
+        env, Test_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_generator/testSingleJNIAdditionalImport.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 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.
 
@@ -19,8 +19,16 @@
 // Step 1: forward declarations.
 namespace {
 const char kFooClassPath[] = "org/chromium/foo/Foo";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Foo_clazz = NULL;
+jclass Foo_clazz(JNIEnv*) { return g_Foo_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
@@ -32,12 +40,12 @@ static void DoSomething(JNIEnv* env, jclass jcaller,
 static base::subtle::AtomicWord g_Foo_calledByNative = 0;
 static void Java_Foo_calledByNative(JNIEnv* env, jobject callback) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_Foo_clazz,
-      g_Foo_clazz);
+  CHECK_CLAZZ(env, Foo_clazz(env),
+      Foo_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_Foo_clazz,
+      env, Foo_clazz(env),
       "calledByNative",
 
 "("
@@ -46,7 +54,7 @@ static void Java_Foo_calledByNative(JNIEnv* env, jobject callback) {
 "V",
       &g_Foo_calledByNative);
 
-     env->CallStaticVoidMethod(g_Foo_clazz,
+     env->CallStaticVoidMethod(Foo_clazz(env),
           method_id, callback);
   jni_generator::CheckException(env);
 
@@ -68,11 +76,11 @@ static bool RegisterNativesImpl(JNIEnv* env) {
 
   const int kMethodsFooSize = arraysize(kMethodsFoo);
 
-  if (env->RegisterNatives(g_Foo_clazz,
+  if (env->RegisterNatives(Foo_clazz(env),
                            kMethodsFoo,
                            kMethodsFooSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Foo_clazz, __FILE__);
+        env, Foo_clazz(env), __FILE__);
     return false;
   }
 

base/android/jni_utils.cc

+// Copyright 2014 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/jni_utils.h"
+
+#include "base/android/jni_android.h"
+#include "base/android/scoped_java_ref.h"
+
+#include "jni/JNIUtils_jni.h"
+
+namespace base {
+namespace android {
+
+ScopedJavaLocalRef<jobject> GetClassLoader(JNIEnv* env) {
+  return Java_JNIUtils_getClassLoader(env);
+}
+
+bool RegisterJNIUtils(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+}  // namespace android
+}  // namespace base
+

base/android/jni_utils.h

+// Copyright 2014 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.
+
+#ifndef BASE_ANDROID_JNI_UTILS_H_
+#define BASE_ANDROID_JNI_UTILS_H_
+
+#include <jni.h>
+
+#include "base/android/scoped_java_ref.h"
+
+namespace base {
+
+namespace android {
+
+// Gets a ClassLoader instance capable of loading Chromium java classes.
+// This should be called either from JNI_OnLoad or from within a method called
+// via JNI from Java.
+BASE_EXPORT ScopedJavaLocalRef<jobject> GetClassLoader(JNIEnv* env);
+
+bool RegisterJNIUtils(JNIEnv* env);
+
+}  // namespace android
+}  // namespace base
+
+#endif  // BASE_ANDROID_JNI_UTILS_H_
+

base/base.gyp

@@ -1282,6 +1282,7 @@
             'android/java/src/org/chromium/base/EventLog.java',
             'android/java/src/org/chromium/base/FieldTrialList.java',
             'android/java/src/org/chromium/base/ImportantFileWriterAndroid.java',
+            'android/java/src/org/chromium/base/JNIUtils.java',
             'android/java/src/org/chromium/base/library_loader/LibraryLoader.java',
             'android/java/src/org/chromium/base/MemoryPressureListener.java',
             'android/java/src/org/chromium/base/JavaHandlerThread.java',

base/base.gypi

@@ -55,6 +55,8 @@
           'android/jni_registrar.h',
           'android/jni_string.cc',
           'android/jni_string.h',
+          'android/jni_utils.cc',
+          'android/jni_utils.h',
           'android/jni_weak_ref.cc',
           'android/jni_weak_ref.h',
           'android/library_loader/library_loader_hooks.cc',

ui/gl/android/scoped_java_surface.cc

@@ -32,7 +32,7 @@ ScopedJavaSurface::ScopedJavaSurface(
       is_protected_(false) {
   JNIEnv* env = base::android::AttachCurrentThread();
   RegisterNativesIfNeeded(env);
-  DCHECK(env->IsInstanceOf(surface.obj(), g_Surface_clazz));
+  DCHECK(env->IsInstanceOf(surface.obj(), Surface_clazz(env)));
   j_surface_.Reset(surface);
 }