test/912-classes/classes.cc - platform/art - Gitiles

 /*
  * Copyright (C) 2013 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include <stdio.h>

 #include <mutex>
 #include <vector>

 #include "android-base/macros.h"
 #include "android-base/stringprintf.h"

 #include "jni.h"
 #include "jvmti.h"

 // Test infrastructure
 #include "jni_helper.h"
 #include "jvmti_helper.h"
 #include "scoped_local_ref.h"
 #include "scoped_utf_chars.h"
 #include "test_env.h"

 namespace art {
 namespace Test912Classes {

 extern "C" JNIEXPORT jboolean JNICALL Java_art_Test912_isModifiableClass(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jboolean res = JNI_FALSE;
   jvmtiError result = jvmti_env->IsModifiableClass(klass, &res);
   JvmtiErrorToException(env, jvmti_env, result);
   return res;
 }

 extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassSignature(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   char* sig;
   char* gen;
   jvmtiError result = jvmti_env->GetClassSignature(klass, &sig, &gen);
   if (JvmtiErrorToException(env, jvmti_env, result)) {
     return nullptr;
   }

   auto callback = [&](jint i) {
     if (i == 0) {
       return sig == nullptr ? nullptr : env->NewStringUTF(sig);
     } else {
       return gen == nullptr ? nullptr : env->NewStringUTF(gen);
     }
   };
   jobjectArray ret = CreateObjectArray(env, 2, "java/lang/String", callback);

   // Need to deallocate the strings.
   if (sig != nullptr) {
     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(sig));
   }
   if (gen != nullptr) {
     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(gen));
   }

   return ret;
 }

 extern "C" JNIEXPORT jboolean JNICALL Java_art_Test912_isInterface(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jboolean is_interface = JNI_FALSE;
   jvmtiError result = jvmti_env->IsInterface(klass, &is_interface);
   JvmtiErrorToException(env, jvmti_env, result);
   return is_interface;
 }

 extern "C" JNIEXPORT jboolean JNICALL Java_art_Test912_isArrayClass(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jboolean is_array_class = JNI_FALSE;
   jvmtiError result = jvmti_env->IsArrayClass(klass, &is_array_class);
   JvmtiErrorToException(env, jvmti_env, result);
   return is_array_class;
 }

 extern "C" JNIEXPORT jint JNICALL Java_art_Test912_getClassModifiers(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jint mod;
   jvmtiError result = jvmti_env->GetClassModifiers(klass, &mod);
   JvmtiErrorToException(env, jvmti_env, result);
   return mod;
 }

 extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassFields(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jint count = 0;
   jfieldID* fields = nullptr;
   jvmtiError result = jvmti_env->GetClassFields(klass, &count, &fields);
   if (JvmtiErrorToException(env, jvmti_env, result)) {
     return nullptr;
   }

   auto callback = [&](jint i) {
     jint modifiers;
     // Ignore any errors for simplicity.
     jvmti_env->GetFieldModifiers(klass, fields[i], &modifiers);
     constexpr jint kStatic = 0x8;
     return env->ToReflectedField(klass,
                                  fields[i],
                                  (modifiers & kStatic) != 0 ? JNI_TRUE : JNI_FALSE);
   };
   jobjectArray ret = CreateObjectArray(env, count, "java/lang/Object", callback);
   if (fields != nullptr) {
     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(fields));
   }
   return ret;
 }

 extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassMethods(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jint count = 0;
   jmethodID* methods = nullptr;
   jvmtiError result = jvmti_env->GetClassMethods(klass, &count, &methods);
   if (JvmtiErrorToException(env, jvmti_env, result)) {
     return nullptr;
   }

   auto callback = [&](jint i) {
     jint modifiers;
     // Ignore any errors for simplicity.
     jvmti_env->GetMethodModifiers(methods[i], &modifiers);
     constexpr jint kStatic = 0x8;
     return env->ToReflectedMethod(klass,
                                   methods[i],
                                   (modifiers & kStatic) != 0 ? JNI_TRUE : JNI_FALSE);
   };
   jobjectArray ret = CreateObjectArray(env, count, "java/lang/Object", callback);
   if (methods != nullptr) {
     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(methods));
   }
   return ret;
 }

 extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getImplementedInterfaces(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jint count = 0;
   jclass* classes = nullptr;
   jvmtiError result = jvmti_env->GetImplementedInterfaces(klass, &count, &classes);
   if (JvmtiErrorToException(env, jvmti_env, result)) {
     return nullptr;
   }

   auto callback = [&](jint i) {
     return classes[i];
   };
   jobjectArray ret = CreateObjectArray(env, count, "java/lang/Class", callback);
   if (classes != nullptr) {
     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(classes));
   }
   return ret;
 }

 extern "C" JNIEXPORT jint JNICALL Java_art_Test912_getClassStatus(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jint status;
   jvmtiError result = jvmti_env->GetClassStatus(klass, &status);
   JvmtiErrorToException(env, jvmti_env, result);
   return status;
 }

 extern "C" JNIEXPORT jobject JNICALL Java_art_Test912_getClassLoader(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jobject classloader;
   jvmtiError result = jvmti_env->GetClassLoader(klass, &classloader);
   JvmtiErrorToException(env, jvmti_env, result);
   return classloader;
 }

 extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassLoaderClasses(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jobject jclassloader) {
   jint count = 0;
   jclass* classes = nullptr;
   jvmtiError result = jvmti_env->GetClassLoaderClasses(jclassloader, &count, &classes);
   if (JvmtiErrorToException(env, jvmti_env, result)) {
     return nullptr;
   }

   auto callback = [&](jint i) {
     return classes[i];
   };
   jobjectArray ret = CreateObjectArray(env, count, "java/lang/Class", callback);
   if (classes != nullptr) {
     jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(classes));
   }
   return ret;
 }

 extern "C" JNIEXPORT jintArray JNICALL Java_art_Test912_getClassVersion(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   jint major, minor;
   jvmtiError result = jvmti_env->GetClassVersionNumbers(klass, &minor, &major);
   if (JvmtiErrorToException(env, jvmti_env, result)) {
     return nullptr;
   }

   jintArray int_array = env->NewIntArray(2);
   if (int_array == nullptr) {
     return nullptr;
   }
   jint buf[2] = { major, minor };
   env->SetIntArrayRegion(int_array, 0, 2, buf);

   return int_array;
 }

 static std::string GetClassName(jvmtiEnv* jenv, JNIEnv* jni_env, jclass klass) {
   char* name;
   jvmtiError result = jenv->GetClassSignature(klass, &name, nullptr);
   if (result != JVMTI_ERROR_NONE) {
     if (jni_env != nullptr) {
       JvmtiErrorToException(jni_env, jenv, result);
     } else {
       printf("Failed to get class signature.\n");
     }
     return "";
   }

   std::string tmp(name);
   jenv->Deallocate(reinterpret_cast<unsigned char*>(name));

   return tmp;
 }

 static void EnableEvents(JNIEnv* env,
                          jboolean enable,
                          decltype(jvmtiEventCallbacks().ClassLoad) class_load,
                          decltype(jvmtiEventCallbacks().ClassPrepare) class_prepare) {
   if (enable == JNI_FALSE) {
     jvmtiError ret = jvmti_env->SetEventNotificationMode(JVMTI_DISABLE,
                                                          JVMTI_EVENT_CLASS_LOAD,
                                                          nullptr);
     if (JvmtiErrorToException(env, jvmti_env, ret)) {
       return;
     }
     ret = jvmti_env->SetEventNotificationMode(JVMTI_DISABLE,
                                               JVMTI_EVENT_CLASS_PREPARE,
                                               nullptr);
     JvmtiErrorToException(env, jvmti_env, ret);
     return;
   }

   jvmtiEventCallbacks callbacks;
   memset(&callbacks, 0, sizeof(jvmtiEventCallbacks));
   callbacks.ClassLoad = class_load;
   callbacks.ClassPrepare = class_prepare;
   jvmtiError ret = jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
   if (JvmtiErrorToException(env, jvmti_env, ret)) {
     return;
   }

   ret = jvmti_env->SetEventNotificationMode(JVMTI_ENABLE,
                                             JVMTI_EVENT_CLASS_LOAD,
                                             nullptr);
   if (JvmtiErrorToException(env, jvmti_env, ret)) {
     return;
   }
   ret = jvmti_env->SetEventNotificationMode(JVMTI_ENABLE,
                                             JVMTI_EVENT_CLASS_PREPARE,
                                             nullptr);
   JvmtiErrorToException(env, jvmti_env, ret);
 }

 static std::mutex gEventsMutex;
 static std::vector<std::string> gEvents;

 extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassLoadMessages(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED) {
   std::lock_guard<std::mutex> guard(gEventsMutex);
   jobjectArray ret = CreateObjectArray(env,
                                        static_cast<jint>(gEvents.size()),
                                        "java/lang/String",
                                        [&](jint i) {
     return env->NewStringUTF(gEvents[i].c_str());
   });
   gEvents.clear();
   return ret;
 }

 class ClassLoadPreparePrinter {
  public:
   static void JNICALL ClassLoadCallback(jvmtiEnv* jenv,
                                         JNIEnv* jni_env,
                                         jthread thread,
                                         jclass klass) {
     std::string name = GetClassName(jenv, jni_env, klass);
     if (name == "") {
       return;
     }
     std::string thread_name = GetThreadName(jenv, jni_env, thread);
     if (thread_name == "") {
       return;
     }
     if (thread_name_filter_ != "" && thread_name_filter_ != thread_name) {
       return;
     }

     std::lock_guard<std::mutex> guard(gEventsMutex);
     gEvents.push_back(android::base::StringPrintf("Load: %s on %s",
                                                   name.c_str(),
                                                   thread_name.c_str()));
   }

   static void JNICALL ClassPrepareCallback(jvmtiEnv* jenv,
                                            JNIEnv* jni_env,
                                            jthread thread,
                                            jclass klass) {
     std::string name = GetClassName(jenv, jni_env, klass);
     if (name == "") {
       return;
     }
     std::string thread_name = GetThreadName(jenv, jni_env, thread);
     if (thread_name == "") {
       return;
     }
     if (thread_name_filter_ != "" && thread_name_filter_ != thread_name) {
       return;
     }
     std::string cur_thread_name = GetThreadName(jenv, jni_env, nullptr);

     std::lock_guard<std::mutex> guard(gEventsMutex);
     gEvents.push_back(android::base::StringPrintf("Prepare: %s on %s (cur=%s)",
                                                   name.c_str(),
                                                   thread_name.c_str(),
                                                   cur_thread_name.c_str()));
   }

   static std::string GetThreadName(jvmtiEnv* jenv, JNIEnv* jni_env, jthread thread) {
     jvmtiThreadInfo info;
     jvmtiError result = jenv->GetThreadInfo(thread, &info);
     if (result != JVMTI_ERROR_NONE) {
       if (jni_env != nullptr) {
         JvmtiErrorToException(jni_env, jenv, result);
       } else {
         printf("Failed to get thread name.\n");
       }
       return "";
     }

     std::string tmp(info.name);
     jenv->Deallocate(reinterpret_cast<unsigned char*>(info.name));
     jni_env->DeleteLocalRef(info.context_class_loader);
     jni_env->DeleteLocalRef(info.thread_group);

     return tmp;
   }

   static std::string thread_name_filter_;
 };
 std::string ClassLoadPreparePrinter::thread_name_filter_;

 extern "C" JNIEXPORT void JNICALL Java_art_Test912_enableClassLoadPreparePrintEvents(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jboolean enable, jthread thread) {
   if (thread != nullptr) {
     ClassLoadPreparePrinter::thread_name_filter_ =
         ClassLoadPreparePrinter::GetThreadName(jvmti_env, env, thread);
   } else {
     ClassLoadPreparePrinter::thread_name_filter_ = "";
   }

   EnableEvents(env,
                enable,
                ClassLoadPreparePrinter::ClassLoadCallback,
                ClassLoadPreparePrinter::ClassPrepareCallback);
 }

 class ClassLoadPrepareEquality {
  public:
   static constexpr const char* kClassName = "Lart/Test912$ClassE;";
   static constexpr const char* kStorageFieldName = "STATIC";
   static constexpr const char* kStorageFieldSig = "Ljava/lang/Object;";
   static constexpr const char* kStorageWeakFieldName = "WEAK";
   static constexpr const char* kStorageWeakFieldSig = "Ljava/lang/ref/Reference;";
   static constexpr const char* kWeakClassName = "java/lang/ref/WeakReference";
   static constexpr const char* kWeakInitSig = "(Ljava/lang/Object;)V";
   static constexpr const char* kWeakGetSig = "()Ljava/lang/Object;";

   static void JNICALL ClassLoadCallback(jvmtiEnv* jenv,
                                         JNIEnv* jni_env,
                                         jthread thread ATTRIBUTE_UNUSED,
                                         jclass klass) {
     std::string name = GetClassName(jenv, jni_env, klass);
     if (name == kClassName) {
       found_ = true;
       stored_class_ = jni_env->NewGlobalRef(klass);
       weakly_stored_class_ = jni_env->NewWeakGlobalRef(klass);
       // The following is bad and relies on implementation details. But otherwise a test would be
       // a lot more complicated.
       local_stored_class_ = jni_env->NewLocalRef(klass);
       // Store the value into a field in the heap.
       SetOrCompare(jni_env, klass, true);
     }
   }

   static void JNICALL ClassPrepareCallback(jvmtiEnv* jenv,
                                            JNIEnv* jni_env,
                                            jthread thread ATTRIBUTE_UNUSED,
                                            jclass klass) {
     std::string name = GetClassName(jenv, jni_env, klass);
     if (name == kClassName) {
       CHECK(stored_class_ != nullptr);
       CHECK(jni_env->IsSameObject(stored_class_, klass));
       CHECK(jni_env->IsSameObject(weakly_stored_class_, klass));
       CHECK(jni_env->IsSameObject(local_stored_class_, klass));
       // Look up the value in a field in the heap.
       SetOrCompare(jni_env, klass, false);
       compared_ = true;
     }
   }

   static void SetOrCompare(JNIEnv* jni_env, jobject value, bool set) {
     CHECK(storage_class_ != nullptr);

     // Simple direct storage.
     jfieldID field = jni_env->GetStaticFieldID(storage_class_, kStorageFieldName, kStorageFieldSig);
     CHECK(field != nullptr);

     if (set) {
       jni_env->SetStaticObjectField(storage_class_, field, value);
       CHECK(!jni_env->ExceptionCheck());
     } else {
       ScopedLocalRef<jobject> stored(jni_env, jni_env->GetStaticObjectField(storage_class_, field));
       CHECK(jni_env->IsSameObject(value, stored.get()));
     }

     // Storage as a reference.
     ScopedLocalRef<jclass> weak_ref_class(jni_env, jni_env->FindClass(kWeakClassName));
     CHECK(weak_ref_class.get() != nullptr);
     jfieldID weak_field = jni_env->GetStaticFieldID(storage_class_,
                                                     kStorageWeakFieldName,
                                                     kStorageWeakFieldSig);
     CHECK(weak_field != nullptr);
     if (set) {
       // Create a WeakReference.
       jmethodID weak_init = jni_env->GetMethodID(weak_ref_class.get(), "<init>", kWeakInitSig);
       CHECK(weak_init != nullptr);
       ScopedLocalRef<jobject> weak_obj(jni_env, jni_env->NewObject(weak_ref_class.get(),
                                                                    weak_init,
                                                                    value));
       CHECK(weak_obj.get() != nullptr);
       jni_env->SetStaticObjectField(storage_class_, weak_field, weak_obj.get());
       CHECK(!jni_env->ExceptionCheck());
     } else {
       // Check the reference value.
       jmethodID get_referent = jni_env->GetMethodID(weak_ref_class.get(), "get", kWeakGetSig);
       CHECK(get_referent != nullptr);
       ScopedLocalRef<jobject> weak_obj(jni_env, jni_env->GetStaticObjectField(storage_class_,
                                                                               weak_field));
       CHECK(weak_obj.get() != nullptr);
       ScopedLocalRef<jobject> weak_referent(jni_env, jni_env->CallObjectMethod(weak_obj.get(),
                                                                                get_referent));
       CHECK(weak_referent.get() != nullptr);
       CHECK(jni_env->IsSameObject(value, weak_referent.get()));
     }
   }

   static void CheckFound() {
     CHECK(found_);
     CHECK(compared_);
   }

   static void Free(JNIEnv* env) {
     if (stored_class_ != nullptr) {
       env->DeleteGlobalRef(stored_class_);
       DCHECK(weakly_stored_class_ != nullptr);
       env->DeleteWeakGlobalRef(weakly_stored_class_);
       // Do not attempt to delete the local ref. It will be out of date by now.
     }
   }

   static jclass storage_class_;

  private:
   static jobject stored_class_;
   static jweak weakly_stored_class_;
   static jobject local_stored_class_;
   static bool found_;
   static bool compared_;
 };
 jclass ClassLoadPrepareEquality::storage_class_ = nullptr;
 jobject ClassLoadPrepareEquality::stored_class_ = nullptr;
 jweak ClassLoadPrepareEquality::weakly_stored_class_ = nullptr;
 jobject ClassLoadPrepareEquality::local_stored_class_ = nullptr;
 bool ClassLoadPrepareEquality::found_ = false;
 bool ClassLoadPrepareEquality::compared_ = false;

 extern "C" JNIEXPORT void JNICALL Java_art_Test912_setEqualityEventStorageClass(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
   ClassLoadPrepareEquality::storage_class_ =
       reinterpret_cast<jclass>(env->NewGlobalRef(klass));
 }

 extern "C" JNIEXPORT void JNICALL Java_art_Test912_enableClassLoadPrepareEqualityEvents(
     JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jboolean b) {
   EnableEvents(env,
                b,
                ClassLoadPrepareEquality::ClassLoadCallback,
                ClassLoadPrepareEquality::ClassPrepareCallback);
   if (b == JNI_FALSE) {
     ClassLoadPrepareEquality::Free(env);
     ClassLoadPrepareEquality::CheckFound();
     env->DeleteGlobalRef(ClassLoadPrepareEquality::storage_class_);
     ClassLoadPrepareEquality::storage_class_ = nullptr;
   }
 }

 }  // namespace Test912Classes
 }  // namespace art
	/*
	* Copyright (C) 2013 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include <stdio.h>

	#include <mutex>
	#include <vector>

	#include "android-base/macros.h"
	#include "android-base/stringprintf.h"

	#include "jni.h"
	#include "jvmti.h"

	// Test infrastructure
	#include "jni_helper.h"
	#include "jvmti_helper.h"
	#include "scoped_local_ref.h"
	#include "scoped_utf_chars.h"
	#include "test_env.h"

	namespace art {
	namespace Test912Classes {

	extern "C" JNIEXPORT jboolean JNICALL Java_art_Test912_isModifiableClass(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jboolean res = JNI_FALSE;
	jvmtiError result = jvmti_env->IsModifiableClass(klass, &res);
	JvmtiErrorToException(env, jvmti_env, result);
	return res;
	}

	extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassSignature(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	char* sig;
	char* gen;
	jvmtiError result = jvmti_env->GetClassSignature(klass, &sig, &gen);
	if (JvmtiErrorToException(env, jvmti_env, result)) {
	return nullptr;
	}

	auto callback = [&](jint i) {
	if (i == 0) {
	return sig == nullptr ? nullptr : env->NewStringUTF(sig);
	} else {
	return gen == nullptr ? nullptr : env->NewStringUTF(gen);
	}
	};
	jobjectArray ret = CreateObjectArray(env, 2, "java/lang/String", callback);

	// Need to deallocate the strings.
	if (sig != nullptr) {
	jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(sig));
	}
	if (gen != nullptr) {
	jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(gen));
	}

	return ret;
	}

	extern "C" JNIEXPORT jboolean JNICALL Java_art_Test912_isInterface(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jboolean is_interface = JNI_FALSE;
	jvmtiError result = jvmti_env->IsInterface(klass, &is_interface);
	JvmtiErrorToException(env, jvmti_env, result);
	return is_interface;
	}

	extern "C" JNIEXPORT jboolean JNICALL Java_art_Test912_isArrayClass(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jboolean is_array_class = JNI_FALSE;
	jvmtiError result = jvmti_env->IsArrayClass(klass, &is_array_class);
	JvmtiErrorToException(env, jvmti_env, result);
	return is_array_class;
	}

	extern "C" JNIEXPORT jint JNICALL Java_art_Test912_getClassModifiers(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jint mod;
	jvmtiError result = jvmti_env->GetClassModifiers(klass, &mod);
	JvmtiErrorToException(env, jvmti_env, result);
	return mod;
	}

	extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassFields(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jint count = 0;
	jfieldID* fields = nullptr;
	jvmtiError result = jvmti_env->GetClassFields(klass, &count, &fields);
	if (JvmtiErrorToException(env, jvmti_env, result)) {
	return nullptr;
	}

	auto callback = [&](jint i) {
	jint modifiers;
	// Ignore any errors for simplicity.
	jvmti_env->GetFieldModifiers(klass, fields[i], &modifiers);
	constexpr jint kStatic = 0x8;
	return env->ToReflectedField(klass,
	fields[i],
	(modifiers & kStatic) != 0 ? JNI_TRUE : JNI_FALSE);
	};
	jobjectArray ret = CreateObjectArray(env, count, "java/lang/Object", callback);
	if (fields != nullptr) {
	jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(fields));
	}
	return ret;
	}

	extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassMethods(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jint count = 0;
	jmethodID* methods = nullptr;
	jvmtiError result = jvmti_env->GetClassMethods(klass, &count, &methods);
	if (JvmtiErrorToException(env, jvmti_env, result)) {
	return nullptr;
	}

	auto callback = [&](jint i) {
	jint modifiers;
	// Ignore any errors for simplicity.
	jvmti_env->GetMethodModifiers(methods[i], &modifiers);
	constexpr jint kStatic = 0x8;
	return env->ToReflectedMethod(klass,
	methods[i],
	(modifiers & kStatic) != 0 ? JNI_TRUE : JNI_FALSE);
	};
	jobjectArray ret = CreateObjectArray(env, count, "java/lang/Object", callback);
	if (methods != nullptr) {
	jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(methods));
	}
	return ret;
	}

	extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getImplementedInterfaces(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jint count = 0;
	jclass* classes = nullptr;
	jvmtiError result = jvmti_env->GetImplementedInterfaces(klass, &count, &classes);
	if (JvmtiErrorToException(env, jvmti_env, result)) {
	return nullptr;
	}

	auto callback = [&](jint i) {
	return classes[i];
	};
	jobjectArray ret = CreateObjectArray(env, count, "java/lang/Class", callback);
	if (classes != nullptr) {
	jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(classes));
	}
	return ret;
	}

	extern "C" JNIEXPORT jint JNICALL Java_art_Test912_getClassStatus(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jint status;
	jvmtiError result = jvmti_env->GetClassStatus(klass, &status);
	JvmtiErrorToException(env, jvmti_env, result);
	return status;
	}

	extern "C" JNIEXPORT jobject JNICALL Java_art_Test912_getClassLoader(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jobject classloader;
	jvmtiError result = jvmti_env->GetClassLoader(klass, &classloader);
	JvmtiErrorToException(env, jvmti_env, result);
	return classloader;
	}

	extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassLoaderClasses(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jobject jclassloader) {
	jint count = 0;
	jclass* classes = nullptr;
	jvmtiError result = jvmti_env->GetClassLoaderClasses(jclassloader, &count, &classes);
	if (JvmtiErrorToException(env, jvmti_env, result)) {
	return nullptr;
	}

	auto callback = [&](jint i) {
	return classes[i];
	};
	jobjectArray ret = CreateObjectArray(env, count, "java/lang/Class", callback);
	if (classes != nullptr) {
	jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(classes));
	}
	return ret;
	}

	extern "C" JNIEXPORT jintArray JNICALL Java_art_Test912_getClassVersion(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	jint major, minor;
	jvmtiError result = jvmti_env->GetClassVersionNumbers(klass, &minor, &major);
	if (JvmtiErrorToException(env, jvmti_env, result)) {
	return nullptr;
	}

	jintArray int_array = env->NewIntArray(2);
	if (int_array == nullptr) {
	return nullptr;
	}
	jint buf[2] = { major, minor };
	env->SetIntArrayRegion(int_array, 0, 2, buf);

	return int_array;
	}

	static std::string GetClassName(jvmtiEnv* jenv, JNIEnv* jni_env, jclass klass) {
	char* name;
	jvmtiError result = jenv->GetClassSignature(klass, &name, nullptr);
	if (result != JVMTI_ERROR_NONE) {
	if (jni_env != nullptr) {
	JvmtiErrorToException(jni_env, jenv, result);
	} else {
	printf("Failed to get class signature.\n");
	}
	return "";
	}

	std::string tmp(name);
	jenv->Deallocate(reinterpret_cast<unsigned char*>(name));

	return tmp;
	}

	static void EnableEvents(JNIEnv* env,
	jboolean enable,
	decltype(jvmtiEventCallbacks().ClassLoad) class_load,
	decltype(jvmtiEventCallbacks().ClassPrepare) class_prepare) {
	if (enable == JNI_FALSE) {
	jvmtiError ret = jvmti_env->SetEventNotificationMode(JVMTI_DISABLE,
	JVMTI_EVENT_CLASS_LOAD,
	nullptr);
	if (JvmtiErrorToException(env, jvmti_env, ret)) {
	return;
	}
	ret = jvmti_env->SetEventNotificationMode(JVMTI_DISABLE,
	JVMTI_EVENT_CLASS_PREPARE,
	nullptr);
	JvmtiErrorToException(env, jvmti_env, ret);
	return;
	}

	jvmtiEventCallbacks callbacks;
	memset(&callbacks, 0, sizeof(jvmtiEventCallbacks));
	callbacks.ClassLoad = class_load;
	callbacks.ClassPrepare = class_prepare;
	jvmtiError ret = jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
	if (JvmtiErrorToException(env, jvmti_env, ret)) {
	return;
	}

	ret = jvmti_env->SetEventNotificationMode(JVMTI_ENABLE,
	JVMTI_EVENT_CLASS_LOAD,
	nullptr);
	if (JvmtiErrorToException(env, jvmti_env, ret)) {
	return;
	}
	ret = jvmti_env->SetEventNotificationMode(JVMTI_ENABLE,
	JVMTI_EVENT_CLASS_PREPARE,
	nullptr);
	JvmtiErrorToException(env, jvmti_env, ret);
	}

	static std::mutex gEventsMutex;
	static std::vector<std::string> gEvents;

	extern "C" JNIEXPORT jobjectArray JNICALL Java_art_Test912_getClassLoadMessages(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED) {
	std::lock_guard<std::mutex> guard(gEventsMutex);
	jobjectArray ret = CreateObjectArray(env,
	static_cast<jint>(gEvents.size()),
	"java/lang/String",
	[&](jint i) {
	return env->NewStringUTF(gEvents[i].c_str());
	});
	gEvents.clear();
	return ret;
	}

	class ClassLoadPreparePrinter {
	public:
	static void JNICALL ClassLoadCallback(jvmtiEnv* jenv,
	JNIEnv* jni_env,
	jthread thread,
	jclass klass) {
	std::string name = GetClassName(jenv, jni_env, klass);
	if (name == "") {
	return;
	}
	std::string thread_name = GetThreadName(jenv, jni_env, thread);
	if (thread_name == "") {
	return;
	}
	if (thread_name_filter_ != "" && thread_name_filter_ != thread_name) {
	return;
	}

	std::lock_guard<std::mutex> guard(gEventsMutex);
	gEvents.push_back(android::base::StringPrintf("Load: %s on %s",
	name.c_str(),
	thread_name.c_str()));
	}

	static void JNICALL ClassPrepareCallback(jvmtiEnv* jenv,
	JNIEnv* jni_env,
	jthread thread,
	jclass klass) {
	std::string name = GetClassName(jenv, jni_env, klass);
	if (name == "") {
	return;
	}
	std::string thread_name = GetThreadName(jenv, jni_env, thread);
	if (thread_name == "") {
	return;
	}
	if (thread_name_filter_ != "" && thread_name_filter_ != thread_name) {
	return;
	}
	std::string cur_thread_name = GetThreadName(jenv, jni_env, nullptr);

	std::lock_guard<std::mutex> guard(gEventsMutex);
	gEvents.push_back(android::base::StringPrintf("Prepare: %s on %s (cur=%s)",
	name.c_str(),
	thread_name.c_str(),
	cur_thread_name.c_str()));
	}

	static std::string GetThreadName(jvmtiEnv* jenv, JNIEnv* jni_env, jthread thread) {
	jvmtiThreadInfo info;
	jvmtiError result = jenv->GetThreadInfo(thread, &info);
	if (result != JVMTI_ERROR_NONE) {
	if (jni_env != nullptr) {
	JvmtiErrorToException(jni_env, jenv, result);
	} else {
	printf("Failed to get thread name.\n");
	}
	return "";
	}

	std::string tmp(info.name);
	jenv->Deallocate(reinterpret_cast<unsigned char*>(info.name));
	jni_env->DeleteLocalRef(info.context_class_loader);
	jni_env->DeleteLocalRef(info.thread_group);

	return tmp;
	}

	static std::string thread_name_filter_;
	};
	std::string ClassLoadPreparePrinter::thread_name_filter_;

	extern "C" JNIEXPORT void JNICALL Java_art_Test912_enableClassLoadPreparePrintEvents(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jboolean enable, jthread thread) {
	if (thread != nullptr) {
	ClassLoadPreparePrinter::thread_name_filter_ =
	ClassLoadPreparePrinter::GetThreadName(jvmti_env, env, thread);
	} else {
	ClassLoadPreparePrinter::thread_name_filter_ = "";
	}

	EnableEvents(env,
	enable,
	ClassLoadPreparePrinter::ClassLoadCallback,
	ClassLoadPreparePrinter::ClassPrepareCallback);
	}

	class ClassLoadPrepareEquality {
	public:
	static constexpr const char* kClassName = "Lart/Test912$ClassE;";
	static constexpr const char* kStorageFieldName = "STATIC";
	static constexpr const char* kStorageFieldSig = "Ljava/lang/Object;";
	static constexpr const char* kStorageWeakFieldName = "WEAK";
	static constexpr const char* kStorageWeakFieldSig = "Ljava/lang/ref/Reference;";
	static constexpr const char* kWeakClassName = "java/lang/ref/WeakReference";
	static constexpr const char* kWeakInitSig = "(Ljava/lang/Object;)V";
	static constexpr const char* kWeakGetSig = "()Ljava/lang/Object;";

	static void JNICALL ClassLoadCallback(jvmtiEnv* jenv,
	JNIEnv* jni_env,
	jthread thread ATTRIBUTE_UNUSED,
	jclass klass) {
	std::string name = GetClassName(jenv, jni_env, klass);
	if (name == kClassName) {
	found_ = true;
	stored_class_ = jni_env->NewGlobalRef(klass);
	weakly_stored_class_ = jni_env->NewWeakGlobalRef(klass);
	// The following is bad and relies on implementation details. But otherwise a test would be
	// a lot more complicated.
	local_stored_class_ = jni_env->NewLocalRef(klass);
	// Store the value into a field in the heap.
	SetOrCompare(jni_env, klass, true);
	}
	}

	static void JNICALL ClassPrepareCallback(jvmtiEnv* jenv,
	JNIEnv* jni_env,
	jthread thread ATTRIBUTE_UNUSED,
	jclass klass) {
	std::string name = GetClassName(jenv, jni_env, klass);
	if (name == kClassName) {
	CHECK(stored_class_ != nullptr);
	CHECK(jni_env->IsSameObject(stored_class_, klass));
	CHECK(jni_env->IsSameObject(weakly_stored_class_, klass));
	CHECK(jni_env->IsSameObject(local_stored_class_, klass));
	// Look up the value in a field in the heap.
	SetOrCompare(jni_env, klass, false);
	compared_ = true;
	}
	}

	static void SetOrCompare(JNIEnv* jni_env, jobject value, bool set) {
	CHECK(storage_class_ != nullptr);

	// Simple direct storage.
	jfieldID field = jni_env->GetStaticFieldID(storage_class_, kStorageFieldName, kStorageFieldSig);
	CHECK(field != nullptr);

	if (set) {
	jni_env->SetStaticObjectField(storage_class_, field, value);
	CHECK(!jni_env->ExceptionCheck());
	} else {
	ScopedLocalRef<jobject> stored(jni_env, jni_env->GetStaticObjectField(storage_class_, field));
	CHECK(jni_env->IsSameObject(value, stored.get()));
	}

	// Storage as a reference.
	ScopedLocalRef<jclass> weak_ref_class(jni_env, jni_env->FindClass(kWeakClassName));
	CHECK(weak_ref_class.get() != nullptr);
	jfieldID weak_field = jni_env->GetStaticFieldID(storage_class_,
	kStorageWeakFieldName,
	kStorageWeakFieldSig);
	CHECK(weak_field != nullptr);
	if (set) {
	// Create a WeakReference.
	jmethodID weak_init = jni_env->GetMethodID(weak_ref_class.get(), "<init>", kWeakInitSig);
	CHECK(weak_init != nullptr);
	ScopedLocalRef<jobject> weak_obj(jni_env, jni_env->NewObject(weak_ref_class.get(),
	weak_init,
	value));
	CHECK(weak_obj.get() != nullptr);
	jni_env->SetStaticObjectField(storage_class_, weak_field, weak_obj.get());
	CHECK(!jni_env->ExceptionCheck());
	} else {
	// Check the reference value.
	jmethodID get_referent = jni_env->GetMethodID(weak_ref_class.get(), "get", kWeakGetSig);
	CHECK(get_referent != nullptr);
	ScopedLocalRef<jobject> weak_obj(jni_env, jni_env->GetStaticObjectField(storage_class_,
	weak_field));
	CHECK(weak_obj.get() != nullptr);
	ScopedLocalRef<jobject> weak_referent(jni_env, jni_env->CallObjectMethod(weak_obj.get(),
	get_referent));
	CHECK(weak_referent.get() != nullptr);
	CHECK(jni_env->IsSameObject(value, weak_referent.get()));
	}
	}

	static void CheckFound() {
	CHECK(found_);
	CHECK(compared_);
	}

	static void Free(JNIEnv* env) {
	if (stored_class_ != nullptr) {
	env->DeleteGlobalRef(stored_class_);
	DCHECK(weakly_stored_class_ != nullptr);
	env->DeleteWeakGlobalRef(weakly_stored_class_);
	// Do not attempt to delete the local ref. It will be out of date by now.
	}
	}

	static jclass storage_class_;

	private:
	static jobject stored_class_;
	static jweak weakly_stored_class_;
	static jobject local_stored_class_;
	static bool found_;
	static bool compared_;
	};
	jclass ClassLoadPrepareEquality::storage_class_ = nullptr;
	jobject ClassLoadPrepareEquality::stored_class_ = nullptr;
	jweak ClassLoadPrepareEquality::weakly_stored_class_ = nullptr;
	jobject ClassLoadPrepareEquality::local_stored_class_ = nullptr;
	bool ClassLoadPrepareEquality::found_ = false;
	bool ClassLoadPrepareEquality::compared_ = false;

	extern "C" JNIEXPORT void JNICALL Java_art_Test912_setEqualityEventStorageClass(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
	ClassLoadPrepareEquality::storage_class_ =
	reinterpret_cast<jclass>(env->NewGlobalRef(klass));
	}

	extern "C" JNIEXPORT void JNICALL Java_art_Test912_enableClassLoadPrepareEqualityEvents(
	JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jboolean b) {
	EnableEvents(env,
	b,
	ClassLoadPrepareEquality::ClassLoadCallback,
	ClassLoadPrepareEquality::ClassPrepareCallback);
	if (b == JNI_FALSE) {
	ClassLoadPrepareEquality::Free(env);
	ClassLoadPrepareEquality::CheckFound();
	env->DeleteGlobalRef(ClassLoadPrepareEquality::storage_class_);
	ClassLoadPrepareEquality::storage_class_ = nullptr;
	}
	}

	} // namespace Test912Classes
	} // namespace art