Android: lazy initialization for method id.

base/android/jni_generator/golden_sample_for_tests_jni.h

 // 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.
 
 // This file is autogenerated by
 //     base/android/jni_generator/jni_generator_tests.py
 // For
 //     org/chromium/example/jni_generator/SampleForTests
 
 #ifndef org_chromium_example_jni_generator_SampleForTests_JNI
 #define org_chromium_example_jni_generator_SampleForTests_JNI
 
 #include <jni.h>
 
 #include "base/android/jni_android.h"
+#include "base/android/jni_method_id.h"
 #include "base/android/scoped_java_ref.h"
 #include "base/basictypes.h"
 #include "base/logging.h"
 
 using base::android::ScopedJavaLocalRef;

[joth, 2012/10/03 17:31:52]

(OT for this CL, but note this is a bug: shouldn't use 'using' in a header file.
Ditto for anon namespace below.)

 
 // Step 1: forward declarations.
 namespace {
 const char kInnerClassClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests$InnerClass";
 const char kSampleForTestsClassPath[] =
     "org/chromium/example/jni_generator/SampleForTests";
 // 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.
@@ skipping 28 matching lines @@
     jint nativeCPPClass) {
   DCHECK(nativeCPPClass) << "Method";
   CPPClass* native = reinterpret_cast<CPPClass*>(nativeCPPClass);
   return native->Method(env, obj);
 }
 
 static jdouble MethodOtherP0(JNIEnv* env, jobject obj,
     jint nativePtr) {
   DCHECK(nativePtr) << "MethodOtherP0";
   CPPClass::InnerClass* native =
-        reinterpret_cast<CPPClass::InnerClass*>(nativePtr);
+      reinterpret_cast<CPPClass::InnerClass*>(nativePtr);
   return native->MethodOtherP0(env, obj);
 }
 
 static jstring InnerMethod(JNIEnv* env, jobject obj,
     jint nativeCPPClass) {
   DCHECK(nativeCPPClass) << "InnerMethod";
   CPPClass* native = reinterpret_cast<CPPClass*>(nativeCPPClass);
   return native->InnerMethod(env, obj).Release();
 }
 
-static jmethodID g_SampleForTests_javaMethod = 0;
+static base::subtle::AtomicWord g_SampleForTests_javaMethod = 0;
 static jint Java_SampleForTests_javaMethod(JNIEnv* env, jobject obj, jint foo,
     jint bar) {
   /* Must call RegisterNativesImpl()  */
   DCHECK(g_SampleForTests_clazz);
-  DCHECK(g_SampleForTests_javaMethod);
-  jint ret =
-    env->CallIntMethod(obj,
-      g_SampleForTests_javaMethod, foo, bar);
-  base::android::CheckException(env);
-  return ret;
-}
+  jmethodID id =
 
-static jmethodID g_SampleForTests_staticJavaMethod = 0;
-static jboolean Java_SampleForTests_staticJavaMethod(JNIEnv* env) {
-  /* Must call RegisterNativesImpl()  */
-  DCHECK(g_SampleForTests_clazz);
-  DCHECK(g_SampleForTests_staticJavaMethod);
-  jboolean ret =
-    env->CallStaticBooleanMethod(g_SampleForTests_clazz,
-      g_SampleForTests_staticJavaMethod);
-  base::android::CheckException(env);
-  return ret;
-}
-
-static jmethodID g_SampleForTests_packagePrivateJavaMethod = 0;
-static void Java_SampleForTests_packagePrivateJavaMethod(JNIEnv* env, jobject
-    obj) {
-  /* Must call RegisterNativesImpl()  */
-  DCHECK(g_SampleForTests_clazz);
-  DCHECK(g_SampleForTests_packagePrivateJavaMethod);
-
-  env->CallVoidMethod(obj,
-      g_SampleForTests_packagePrivateJavaMethod);
-  base::android::CheckException(env);
-
-}
-
-static jmethodID g_SampleForTests_methodThatThrowsException = 0;
-static void Java_SampleForTests_methodThatThrowsException(JNIEnv* env, jobject
-    obj) {
-  /* Must call RegisterNativesImpl()  */
-  DCHECK(g_SampleForTests_clazz);
-  DCHECK(g_SampleForTests_methodThatThrowsException);
-
-  env->CallVoidMethod(obj,
-      g_SampleForTests_methodThatThrowsException);
-
-}
-
-static jmethodID g_InnerClass_JavaInnerMethod = 0;
-static jfloat Java_InnerClass_JavaInnerMethod(JNIEnv* env, jobject obj) {
-  /* Must call RegisterNativesImpl()  */
-  DCHECK(g_InnerClass_clazz);
-  DCHECK(g_InnerClass_JavaInnerMethod);
-  jfloat ret =
-    env->CallFloatMethod(obj,
-      g_InnerClass_JavaInnerMethod);
-  base::android::CheckException(env);
-  return ret;
-}
-
-static jmethodID g_InnerClass_javaInnerFunction = 0;
-static void Java_InnerClass_javaInnerFunction(JNIEnv* env) {
-  /* Must call RegisterNativesImpl()  */
-  DCHECK(g_InnerClass_clazz);
-  DCHECK(g_InnerClass_javaInnerFunction);
-
-  env->CallStaticVoidMethod(g_InnerClass_clazz,
-      g_InnerClass_javaInnerFunction);
-  base::android::CheckException(env);
-
-}
-
-// Step 3: GetMethodIDs and RegisterNatives.
-static void GetMethodIDsImpl(JNIEnv* env) {
-  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",
+  base::android::MethodID::LazyGet<
+      base::android::MethodID::METHODTYPE_NORMAL,
+      base::android::MethodID::EXCEPTIONCHECK_YES>(
+      env, g_SampleForTests_clazz,
+      "javaMethod",
 
 "("
 "I"
 "I"
 ")"
-"I");
+"I",
+      &g_SampleForTests_javaMethod);
 
-  g_SampleForTests_staticJavaMethod =
-      base::android::GetStaticMethodID(
-          env, g_SampleForTests_clazz,
-          "staticJavaMethod",
+  jint ret =
+    env->CallIntMethod(obj,
+      id, foo, bar);
+  base::android::CheckException(env);
+  return ret;
+}
+
+static base::subtle::AtomicWord g_SampleForTests_staticJavaMethod = 0;
+static jboolean Java_SampleForTests_staticJavaMethod(JNIEnv* env) {
+  /* Must call RegisterNativesImpl()  */
+  DCHECK(g_SampleForTests_clazz);
+  jmethodID id =
+
+  base::android::MethodID::LazyGet<

[joth, 2012/10/03 17:31:52]

nit: can this go on the same line as "jmethodID id =" ?

+      base::android::MethodID::METHODTYPE_STATIC,
+      base::android::MethodID::EXCEPTIONCHECK_YES>(
+      env, g_SampleForTests_clazz,
+      "staticJavaMethod",
 
 "("
 ")"
-"Z");
+"Z",
+      &g_SampleForTests_staticJavaMethod);
 
-  g_SampleForTests_packagePrivateJavaMethod =
-      base::android::GetMethodID(
-          env, g_SampleForTests_clazz,
-          "packagePrivateJavaMethod",
+  jboolean ret =
+    env->CallStaticBooleanMethod(g_SampleForTests_clazz,
+      id);
+  base::android::CheckException(env);
+  return ret;
+}
+
+static base::subtle::AtomicWord g_SampleForTests_packagePrivateJavaMethod = 0;
+static void Java_SampleForTests_packagePrivateJavaMethod(JNIEnv* env, jobject
+    obj) {
+  /* Must call RegisterNativesImpl()  */
+  DCHECK(g_SampleForTests_clazz);
+  jmethodID id =
+
+  base::android::MethodID::LazyGet<
+      base::android::MethodID::METHODTYPE_NORMAL,
+      base::android::MethodID::EXCEPTIONCHECK_YES>(
+      env, g_SampleForTests_clazz,
+      "packagePrivateJavaMethod",
 
 "("
 ")"
-"V");
+"V",
+      &g_SampleForTests_packagePrivateJavaMethod);
 
-  g_SampleForTests_methodThatThrowsException =
-      base::android::GetMethodID(
-          env, g_SampleForTests_clazz,
-          "methodThatThrowsException",
+  env->CallVoidMethod(obj,
+      id);
+  base::android::CheckException(env);
+
+}
+
+static base::subtle::AtomicWord g_SampleForTests_methodThatThrowsException = 0;
+static void Java_SampleForTests_methodThatThrowsException(JNIEnv* env, jobject
+    obj) {
+  /* Must call RegisterNativesImpl()  */
+  DCHECK(g_SampleForTests_clazz);
+  jmethodID id =
+
+  base::android::MethodID::LazyGet<
+      base::android::MethodID::METHODTYPE_NORMAL,
+      base::android::MethodID::EXCEPTIONCHECK_YES>(
+      env, g_SampleForTests_clazz,
+      "methodThatThrowsException",
 
 "("
 ")"
-"V");
+"V",
+      &g_SampleForTests_methodThatThrowsException);
 
-  g_InnerClass_JavaInnerMethod =
-      base::android::GetMethodID(
-          env, g_InnerClass_clazz,
-          "JavaInnerMethod",
+  env->CallVoidMethod(obj,
+      id);
+
+}
+
+static base::subtle::AtomicWord g_InnerClass_JavaInnerMethod = 0;
+static jfloat Java_InnerClass_JavaInnerMethod(JNIEnv* env, jobject obj) {
+  /* Must call RegisterNativesImpl()  */
+  DCHECK(g_InnerClass_clazz);
+  jmethodID id =
+
+  base::android::MethodID::LazyGet<
+      base::android::MethodID::METHODTYPE_NORMAL,
+      base::android::MethodID::EXCEPTIONCHECK_YES>(
+      env, g_InnerClass_clazz,
+      "JavaInnerMethod",
 
 "("
 ")"
-"F");
+"F",
+      &g_InnerClass_JavaInnerMethod);
 
-  g_InnerClass_javaInnerFunction =
-      base::android::GetStaticMethodID(
-          env, g_InnerClass_clazz,
-          "javaInnerFunction",
+  jfloat ret =
+    env->CallFloatMethod(obj,
+      id);
+  base::android::CheckException(env);
+  return ret;
+}
+
+static base::subtle::AtomicWord g_InnerClass_javaInnerFunction = 0;
+static void Java_InnerClass_javaInnerFunction(JNIEnv* env) {
+  /* Must call RegisterNativesImpl()  */
+  DCHECK(g_InnerClass_clazz);
+  jmethodID id =
+
+  base::android::MethodID::LazyGet<
+      base::android::MethodID::METHODTYPE_STATIC,
+      base::android::MethodID::EXCEPTIONCHECK_YES>(
+      env, g_InnerClass_clazz,
+      "javaInnerFunction",
 
 "("
 ")"
-"V");
+"V",
+      &g_InnerClass_javaInnerFunction);
+
+  env->CallStaticVoidMethod(g_InnerClass_clazz,
+      id);
+  base::android::CheckException(env);
 
 }
 
+// Step 3: RegisterNatives.
+
 static bool RegisterNativesImpl(JNIEnv* env) {
-  GetMethodIDsImpl(env);
 
+  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)));
   static const JNINativeMethod kMethodsInnerClass[] = {
     { "nativeInnerFunction",
 "("
 ")"
 "I", reinterpret_cast<void*>(InnerFunction) },
     { "nativeInnerMethod",
 "("
 "I"
 ")"
 "Ljava/lang/String;", reinterpret_cast<void*>(InnerMethod) },
@@ skipping 53 matching lines @@
     LOG(ERROR) << "RegisterNatives failed in " << __FILE__;
     return false;
   }
 
   return true;
 }
 }  // namespace android
 }  // namespace base
 
 #endif  // org_chromium_example_jni_generator_SampleForTests_JNI