C++ Persistent类代码示例

  /*
   * This is meant to run one time when the match creator is initialized.
   */
  void customScriptInit()
  {
    Context::Scope context_scope(_script->getContext());
    HandleScope handleScope;

    Persistent<Object> plugin = getPlugin();
    Handle<String> initStr = String::New("init");
    if (plugin->Has(initStr) == false)
    {
      throw HootException("Error finding 'init' function.");
    }
    Handle<v8::Value> value = plugin->Get(initStr);
    if (value->IsFunction() == false)
    {
      throw HootException("init is not a function.");
    }

    Handle<v8::Function> func = v8::Handle<v8::Function>::Cast(value);
    Handle<Value> jsArgs[1];
    int argc = 0;
    HandleScope scope;
    assert(_map.get());
    OsmMapPtr copiedMap(new OsmMap(_map));
    jsArgs[argc++] = OsmMapJs::create(copiedMap);

    func->Call(plugin, argc, jsArgs);

    //this is meant to have been set externally in a js rules file
    _searchRadius = getNumber(plugin, "searchRadius", -1.0, 15.0);
  }

MatchCreator::Description ScriptMatchCreator::_getScriptDescription(QString path) const
{
  MatchCreator::Description result;
  result.experimental = true;

  shared_ptr<PluginContext> script(new PluginContext());
  HandleScope handleScope;
  Context::Scope context_scope(script->getContext());
  script->loadScript(path, "plugin");

  Persistent<Object> plugin = ScriptMatchVisitor::getPlugin(script);
  Handle<String> descriptionStr = String::New("description");
  if (plugin->Has(descriptionStr))
  {
    Handle<v8::Value> value = plugin->Get(descriptionStr);
    result.description = toCpp<QString>(value);
  }
  Handle<String> experimentalStr = String::New("experimental");
  if (plugin->Has(experimentalStr))
  {
    Handle<v8::Value> value = plugin->Get(experimentalStr);
    result.experimental = toCpp<bool>(value);
  }

  QFileInfo fi(path);
  result.className = (QString::fromStdString(className()) + "," + fi.fileName()).toStdString();

  return result;
}

/*
 * Class:     org_appcelerator_kroll_runtime_v8_V8Runtime
 * Method:    nativeRunModule
 * Signature: (Ljava/lang/String;Ljava/lang/String;)V
 */
JNIEXPORT void JNICALL Java_org_appcelerator_kroll_runtime_v8_V8Runtime_nativeRunModule
	(JNIEnv *env, jobject self, jstring source, jstring filename, jobject activityProxy)
{
	ENTER_V8(V8Runtime::globalContext);
	titanium::JNIScope jniScope(env);

	if (moduleObject.IsEmpty()) {
		moduleObject = Persistent<Object>::New(
			V8Runtime::krollGlobalObject->Get(String::New("Module"))->ToObject());

		runModuleFunction = Persistent<Function>::New(
			Handle<Function>::Cast(moduleObject->Get(String::New("runModule"))));
	}

	Handle<Value> jsSource = TypeConverter::javaStringToJsString(source);
	Handle<Value> jsFilename = TypeConverter::javaStringToJsString(filename);
	Handle<Value> jsActivity = TypeConverter::javaObjectToJsValue(activityProxy);

	Handle<Value> args[] = { jsSource, jsFilename, jsActivity };
	TryCatch tryCatch;

	runModuleFunction->Call(moduleObject, 3, args);

	if (tryCatch.HasCaught()) {
		V8Util::openJSErrorDialog(tryCatch);
		V8Util::reportException(tryCatch, true);
	}
}

TEST(ImageResourceTest, SuccessfulRevalidationSvg) {
  KURL url(ParsedURLString, "http://127.0.0.1:8000/foo");
  ImageResource* imageResource = ImageResource::create(ResourceRequest(url));
  Persistent<MockImageResourceClient> client =
      new MockImageResourceClient(imageResource);

  receiveResponse(imageResource, url, "image/svg+xml", svgImage());

  EXPECT_FALSE(imageResource->errorOccurred());
  ASSERT_TRUE(imageResource->hasImage());
  EXPECT_FALSE(imageResource->getImage()->isNull());
  EXPECT_EQ(1, client->imageChangedCount());
  EXPECT_TRUE(client->notifyFinishedCalled());
  EXPECT_FALSE(imageResource->getImage()->isBitmapImage());
  EXPECT_EQ(200, imageResource->getImage()->width());
  EXPECT_EQ(200, imageResource->getImage()->height());

  imageResource->setRevalidatingRequest(ResourceRequest(url));
  ResourceResponse response;
  response.setURL(url);
  response.setHTTPStatusCode(304);
  imageResource->responseReceived(response, nullptr);

  EXPECT_FALSE(imageResource->errorOccurred());
  ASSERT_TRUE(imageResource->hasImage());
  EXPECT_FALSE(imageResource->getImage()->isNull());
  EXPECT_EQ(1, client->imageChangedCount());
  EXPECT_TRUE(client->notifyFinishedCalled());
  EXPECT_FALSE(imageResource->getImage()->isBitmapImage());
  EXPECT_EQ(200, imageResource->getImage()->width());
  EXPECT_EQ(200, imageResource->getImage()->height());
}

TEST(ImageResourceTest, DecodedDataRemainsWhileHasClients)
{
    ImageResource* cachedImage = ImageResource::create(ResourceRequest());
    cachedImage->setStatus(Resource::Pending);

    Persistent<MockImageResourceClient> client = new MockImageResourceClient(cachedImage);

    // Send the image response.
    cachedImage->responseReceived(ResourceResponse(KURL(), "multipart/x-mixed-replace", 0, nullAtom, String()), nullptr);

    Vector<unsigned char> jpeg = jpegImage();
    cachedImage->responseReceived(ResourceResponse(KURL(), "image/jpeg", jpeg.size(), nullAtom, String()), nullptr);
    cachedImage->appendData(reinterpret_cast<const char*>(jpeg.data()), jpeg.size());
    cachedImage->finish();
    ASSERT_FALSE(cachedImage->errorOccurred());
    ASSERT_TRUE(cachedImage->hasImage());
    ASSERT_FALSE(cachedImage->getImage()->isNull());
    ASSERT_TRUE(client->notifyFinishedCalled());

    // The prune comes when the ImageResource still has clients. The image should not be deleted.
    cachedImage->prune();
    ASSERT_TRUE(cachedImage->hasClientsOrObservers());
    ASSERT_TRUE(cachedImage->hasImage());
    ASSERT_FALSE(cachedImage->getImage()->isNull());

    // The ImageResource no longer has clients. The image should be deleted by prune.
    client->removeAsClient();
    cachedImage->prune();
    ASSERT_FALSE(cachedImage->hasClientsOrObservers());
    ASSERT_FALSE(cachedImage->hasImage());
    ASSERT_TRUE(cachedImage->getImage()->isNull());
}

void
test_obj_setprop()
{
  HandleScope handle_scope;

  Persistent<Context> context = Context::New();

  Context::Scope context_scope(context);

  Handle<Object> obj = Object::New();

  Handle<String> k = String::New("someprop");
  Handle<String> v = String::New("somevalue");

  obj->Set(k, v);

  Handle<Value> v2 = obj->Get(k);

  String::AsciiValue vs(v);
  String::AsciiValue vs2(v2);

  do_check_eq(vs.length(), vs2.length());
  do_check_eq(0, strcmp(*vs,*vs2));

  context.Dispose();
}

void Init (Handle<Object> target) {
  
  initQueues();
  freeThreadsQueue= nuQueue(-3); //闲置线程队列的 id为 -3
  freeJobsQueue= nuQueue(-4); //闲置任务队列的id 为-4
  
  HandleScope scope;
  
  //static bool   IsActive ()
  //将返回当前V8的运行实例是否加锁
  useLocker= v8::Locker::IsActive(); 
  

  target->Set(String::NewSymbol("create"), FunctionTemplate::New(Create)->GetFunction());
  target->Set(String::NewSymbol("createPool"), Script::Compile(String::New(kCreatePool_js))->Run()->ToObject());
  //target->Set(String::NewSymbol("JASON"), Script::Compile(String::New(kJASON_js))->Run()->ToObject());
  
  //设置js访问线程id的属性名为‘id’
  id_symbol= Persistent<String>::New(String::NewSymbol("id"));
  
  //定义 threadTemplate 的一些属性
  threadTemplate= Persistent<ObjectTemplate>::New(ObjectTemplate::New());
  threadTemplate->SetInternalFieldCount(1);
  threadTemplate->Set(id_symbol, Integer::New(0));
  threadTemplate->Set(String::NewSymbol("eval"), FunctionTemplate::New(Eval));
  //threadTemplate->Set(String::NewSymbol("load"), FunctionTemplate::New(Load));
  threadTemplate->Set(String::NewSymbol("emit"), FunctionTemplate::New(processEmit));
  threadTemplate->Set(String::NewSymbol("destroy"), FunctionTemplate::New(Destroy));
}

// initialize a JS wrapper around this object
void NodeFSEvents::Initialize(Handle<Object> target)
{
    HandleScope scope;
    emit_sym = NODE_PSYMBOL("emit");
    change_sym = NODE_PSYMBOL("fsevent");
    Local<FunctionTemplate> t = FunctionTemplate::New(NodeFSEvents::New);
    constructor_template = Persistent<FunctionTemplate>::New(t);
    constructor_template->InstanceTemplate()->SetInternalFieldCount(1);
    constructor_template->SetClassName(String::NewSymbol("FSEvents"));
    Local<Function> constructor = constructor_template->GetFunction();

    constructor->Set(String::New("kFSEventStreamEventFlagNone"), Integer::New(0x00000000));
    constructor->Set(String::New("kFSEventStreamEventFlagMustScanSubDirs"), Integer::New(0x00000001));
    constructor->Set(String::New("kFSEventStreamEventFlagUserDropped"), Integer::New(0x00000002));
    constructor->Set(String::New("kFSEventStreamEventFlagKernelDropped"), Integer::New(0x00000004));
    constructor->Set(String::New("kFSEventStreamEventFlagEventIdsWrapped"), Integer::New(0x00000008));
    constructor->Set(String::New("kFSEventStreamEventFlagHistoryDone"), Integer::New(0x00000010));
    constructor->Set(String::New("kFSEventStreamEventFlagRootChanged"), Integer::New(0x00000020));
    constructor->Set(String::New("kFSEventStreamEventFlagMount"), Integer::New(0x00000040));
    constructor->Set(String::New("kFSEventStreamEventFlagUnmount"), Integer::New(0x00000080));
    constructor->Set(String::New("kFSEventStreamEventFlagItemCreated"), Integer::New(0x00000100));
    constructor->Set(String::New("kFSEventStreamEventFlagItemRemoved"), Integer::New(0x00000200));
    constructor->Set(String::New("kFSEventStreamEventFlagItemInodeMetaMod"), Integer::New(0x00000400));
    constructor->Set(String::New("kFSEventStreamEventFlagItemRenamed"), Integer::New(0x00000800));
    constructor->Set(String::New("kFSEventStreamEventFlagItemModified"), Integer::New(0x00001000));
    constructor->Set(String::New("kFSEventStreamEventFlagItemFinderInfoMod"), Integer::New(0x00002000));
    constructor->Set(String::New("kFSEventStreamEventFlagItemChangeOwner"), Integer::New(0x00004000));
    constructor->Set(String::New("kFSEventStreamEventFlagItemXattrMod"), Integer::New(0x00008000));
    constructor->Set(String::New("kFSEventStreamEventFlagItemIsFile"), Integer::New(0x00010000));
    constructor->Set(String::New("kFSEventStreamEventFlagItemIsDir"), Integer::New(0x00020000));
    constructor->Set(String::New("kFSEventStreamEventFlagItemIsSymlink"), Integer::New(0x00040000));

    target->Set(String::NewSymbol("FSEvents"), constructor);
}

Handle<Value> HashTable::Put(const Arguments& args) {
  HandleScope scope;

  HashTable *obj = ObjectWrap::Unwrap<HashTable>(args.This());

  Local<Value> key = Local<Value>(args[0]);
  Local<Value> value = Local<Value>(args[1]);

  String::AsciiValue keyStr(key);

  MapType::const_iterator itr = obj->map.find(std::string(*keyStr));

  //overwriting an existing value
  if(itr != obj->map.end()) {
    Persistent<Value> oldValue = itr->second;
    oldValue.Dispose(); //release the handle to the GC
  } 

  Persistent<Value> persistent = Persistent<Value>::New(value);

  obj->map.insert(std::pair<std::string, Persistent<Value> >(std::string(*keyStr), persistent));

  //Return undefined
  return scope.Close(Local<Value>());
}

Handle<Value> WrappedScript::CreateContext(const Arguments& args)
{
	HandleScope scope;

	Persistent<Context> context = Context::New(NULL, WrappedContext::global_template);
	WrappedContext *wrappedContext = new WrappedContext(context);
	Local<Object> global = context->Global();

	// Allow current context access to newly created context's objects.
	context->SetSecurityToken(Context::GetCurrent()->GetSecurityToken());

	// If a sandbox is provided initial the new context's global with it.
	if (args.Length() > 0) {
		Local<Object> sandbox = args[0]->ToObject();
		Local<Array> keys = sandbox->GetPropertyNames();

		for (uint32_t i = 0; i < keys->Length(); i++) {
			Handle<String> key = keys->Get(Integer::New(i))->ToString();
			Handle<Value> value = sandbox->Get(key);
			if (value == sandbox) {
				value = global;
			}
			global->Set(key, value);
		}
	}

	return scope.Close(global);
}

void NovaNode::DoneWithSuspectCallback(Persistent<Value> suspect, void *paramater) {
	Suspect *s = static_cast<Suspect*>(paramater);
	delete s;	
	suspect.ClearWeak();
	suspect.Dispose();
	suspect.Clear();
}

extern "C" Handle<Value> execute_string(Persistent<Context> context,
					const char* s,
					bool* is_exception) {
    // Create a stack-allocated handle scope.
    HandleScope handle_scope;

    // Enter the created context for compiling and
    // running the hello world script.
    Context::Scope context_scope(context);

    // Create a string containing the JavaScript source code.
    Handle<String> source = String::New(s);

    // Compile it
    Handle<Script> script = Script::Compile(source);

    // try-catch handler
    TryCatch trycatch;
    // Run it
    Persistent<Value> result = Persistent<Value>::New(script->Run());

    // Script->Run() returns an empty handle if the code threw an exception
    if (result.IsEmpty()) {
	*is_exception = true;
	Handle<Value> exception = trycatch.Exception();
	// String::AsciiValue exception_str(exception);
	return Persistent<Value>::New(exception);	
    }
    
    return result;
}

void
test_WriteAscii()
{
  HandleScope handle_scope;
  Persistent<Context> context = Context::New();
  Context::Scope context_scope(context);

  char TEST_STRING[] = "this is a UTF-8 test!  This is pi: π";
  int TEST_LENGTH = strlen(TEST_STRING);
  Handle<String> str = String::New(TEST_STRING);
  char* buf = new char[TEST_LENGTH * 2];

  // Iterate over the entire string and use it as the start.
  int EXPECTED_LENGTH = TEST_LENGTH - 1; // We should drop the UTF-8 char.
  for (int start = 0; start < TEST_LENGTH; start++) {
    // Fill the buffer with 'a' to ensure there are no NULLs to start with.
    fill_string(buf, 'a', TEST_LENGTH * 2);
    int copied = str->WriteAscii(buf, start, TEST_LENGTH * 2);
    do_check_eq(copied, EXPECTED_LENGTH - start);
    do_check_eq(strlen(buf), EXPECTED_LENGTH - start);
  }

  delete[] buf;
  context.Dispose();
}

void ScanHelper_initOnLoad(Handle<Object> target) {
  Persistent<Object> scanObj = Persistent<Object>(Object::New());
  Persistent<String> scanKey = Persistent<String>(String::NewSymbol("Scan"));
  target->Set(scanKey, scanObj);

  DEFINE_JS_FUNCTION(scanObj, "create", DBScanHelper_wrapper);

  Persistent<Object> ScanHelper = Persistent<Object>(Object::New());
  Persistent<Object> ScanFlags = Persistent<Object>(Object::New());
  
  scanObj->Set(Persistent<String>(String::NewSymbol("helper")), ScanHelper);
  scanObj->Set(Persistent<String>(String::NewSymbol("flags")), ScanFlags);

  WRAP_CONSTANT(ScanFlags, SF_TupScan);
  WRAP_CONSTANT(ScanFlags, SF_DiskScan);
  WRAP_CONSTANT(ScanFlags, SF_OrderBy);
  WRAP_CONSTANT(ScanFlags, SF_OrderByFull);
  WRAP_CONSTANT(ScanFlags, SF_Descending);
  WRAP_CONSTANT(ScanFlags, SF_ReadRangeNo);
  WRAP_CONSTANT(ScanFlags, SF_MultiRange);
  WRAP_CONSTANT(ScanFlags, SF_KeyInfo);
  
  DEFINE_JS_INT(ScanHelper, "table_record", SCAN_TABLE_RECORD);
  DEFINE_JS_INT(ScanHelper, "index_record", SCAN_INDEX_RECORD);
  DEFINE_JS_INT(ScanHelper, "lock_mode", SCAN_LOCK_MODE);
  DEFINE_JS_INT(ScanHelper, "bounds", SCAN_BOUNDS);
  DEFINE_JS_INT(ScanHelper, "flags", SCAN_OPTION_FLAGS);
  DEFINE_JS_INT(ScanHelper, "batch_size", SCAN_OPTION_BATCH_SIZE);
  DEFINE_JS_INT(ScanHelper, "parallel", SCAN_OPTION_PARALLELISM);
  DEFINE_JS_INT(ScanHelper, "filter_code", SCAN_FILTER_CODE);
}

/* called by the Java environment for objects that have been finalized */
void Conv::releaseV8Handle(JNIEnv *jniEnv, Persistent<Object> val, int type) {
  HandleScope scope;
  Handle<String> sHiddenKey;
  Interface *interface = 0;
  ArrayType *arr = 0;
  if(type == -1) {
    sHiddenKey = sObjectHiddenKey;
  } else if(isArray(type)) {
    arrayConv->GetRefsForComponentType(jniEnv, getComponentType(type), &arr);
    sHiddenKey = arr->getHiddenKey();
  } else if(isInterface(type)) {
    interface = env->getInterface(getClassId(type));
    sHiddenKey = interface->getHiddenKey();
  }
  //LOGV("releaseV8Handle; interface = %p; getting hidden value; sHiddenKey = %p\n", interface, sHiddenKey);
  if(!sHiddenKey.IsEmpty()) {
    Local<Value> hiddenVal = val->GetHiddenValue(sHiddenKey);
    if(!hiddenVal.IsEmpty() && !hiddenVal->IsUndefined()) {
      jobject extRef = (jobject)External::Unwrap(hiddenVal);
      Conv::deleteGlobalRef(jniEnv, extRef);
      val->DeleteHiddenValue(sHiddenKey);
      if(interface) {
        while((interface = interface->getParent())) {
          val->DeleteHiddenValue(interface->getHiddenKey());
        }
      }
    }
  }
  val.Dispose();
}