dubbo的WrappedChannelHandler有什么作用
本篇内容介绍了“dubbo的WrappedChannelHandler有什么作用”的有关知识，在实际案例的操作过程中，不少人都会遇到这样的困境，接下来就让小编带领大家学习一下如何处理这些情况吧！希望大家仔细阅读，能够学有所成！
创新互联建站是一家企业级云计算解决方案提供商,超15年IDC数据中心运营经验。主营GPU显卡服务器，站群服务器，移动服务器托管，海外高防服务器，机柜大带宽，动态拨号VPS，海外云手机，海外云服务器，海外服务器租用托管等。
序
本文主要研究一下dubbo的WrappedChannelHandler
WrappedChannelHandler
dubbo-2.7.3/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/dispatcher/WrappedChannelHandler.java
public class WrappedChannelHandler implements ChannelHandlerDelegate {
protected static final Logger logger = LoggerFactory.getLogger(WrappedChannelHandler.class);
protected static final ExecutorService SHARED_EXECUTOR = Executors.newCachedThreadPool(new NamedThreadFactory("DubboSharedHandler", true));
protected final ExecutorService executor;
protected final ChannelHandler handler;
protected final URL url;
public WrappedChannelHandler(ChannelHandler handler, URL url) {
this.handler = handler;
this.url = url;
executor = (ExecutorService) ExtensionLoader.getExtensionLoader(ThreadPool.class).getAdaptiveExtension().getExecutor(url);
String componentKey = Constants.EXECUTOR_SERVICE_COMPONENT_KEY;
if (CONSUMER_SIDE.equalsIgnoreCase(url.getParameter(SIDE_KEY))) {
componentKey = CONSUMER_SIDE;
}
DataStore dataStore = ExtensionLoader.getExtensionLoader(DataStore.class).getDefaultExtension();
dataStore.put(componentKey, Integer.toString(url.getPort()), executor);
}
public void close() {
try {
if (executor != null) {
executor.shutdown();
}
} catch (Throwable t) {
logger.warn("fail to destroy thread pool of server: " + t.getMessage(), t);
}
}
@Override
public void connected(Channel channel) throws RemotingException {
handler.connected(channel);
}
@Override
public void disconnected(Channel channel) throws RemotingException {
handler.disconnected(channel);
}
@Override
public void sent(Channel channel, Object message) throws RemotingException {
handler.sent(channel, message);
}
@Override
public void received(Channel channel, Object message) throws RemotingException {
handler.received(channel, message);
}
@Override
public void caught(Channel channel, Throwable exception) throws RemotingException {
handler.caught(channel, exception);
}
public ExecutorService getExecutor() {
return executor;
}
@Override
public ChannelHandler getHandler() {
if (handler instanceof ChannelHandlerDelegate) {
return ((ChannelHandlerDelegate) handler).getHandler();
} else {
return handler;
}
}
public URL getUrl() {
return url;
}
public ExecutorService getExecutorService() {
ExecutorService cexecutor = executor;
if (cexecutor == null || cexecutor.isShutdown()) {
cexecutor = SHARED_EXECUTOR;
}
return cexecutor;
}
}WrappedChannelHandler的构造根据ExtensionLoader.getExtensionLoader(ThreadPool.class).getAdaptiveExtension().getExecutor(url)获取ExecutorService，然后放到dataStore中
ExecutionChannelHandler
dubbo-2.7.3/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/dispatcher/execution/ExecutionChannelHandler.java
public class ExecutionChannelHandler extends WrappedChannelHandler {
public ExecutionChannelHandler(ChannelHandler handler, URL url) {
super(handler, url);
}
@Override
public void received(Channel channel, Object message) throws RemotingException {
ExecutorService executor = getExecutorService();
if (message instanceof Request) {
try {
executor.execute(new ChannelEventRunnable(channel, handler, ChannelState.RECEIVED, message));
} catch (Throwable t) {
// FIXME: when the thread pool is full, SERVER_THREADPOOL_EXHAUSTED_ERROR cannot return properly,
// therefore the consumer side has to wait until gets timeout. This is a temporary solution to prevent
// this scenario from happening, but a better solution should be considered later.
if (t instanceof RejectedExecutionException) {
Request request = (Request) message;
if (request.isTwoWay()) {
String msg = "Server side(" + url.getIp() + "," + url.getPort()
+ ") thread pool is exhausted, detail msg:" + t.getMessage();
Response response = new Response(request.getId(), request.getVersion());
response.setStatus(Response.SERVER_THREADPOOL_EXHAUSTED_ERROR);
response.setErrorMessage(msg);
channel.send(response);
return;
}
}
throw new ExecutionException(message, channel, getClass() + " error when process received event.", t);
}
} else {
handler.received(channel, message);
}
}
}ExecutionChannelHandler继承了WrappedChannelHandler，其received会创建ChannelEventRunnable，然后放到executor去执行
ChannelEventRunnable
dubbo-2.7.3/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/dispatcher/ChannelEventRunnable.java
public class ChannelEventRunnable implements Runnable {
private static final Logger logger = LoggerFactory.getLogger(ChannelEventRunnable.class);
private final ChannelHandler handler;
private final Channel channel;
private final ChannelState state;
private final Throwable exception;
private final Object message;
public ChannelEventRunnable(Channel channel, ChannelHandler handler, ChannelState state) {
this(channel, handler, state, null);
}
public ChannelEventRunnable(Channel channel, ChannelHandler handler, ChannelState state, Object message) {
this(channel, handler, state, message, null);
}
public ChannelEventRunnable(Channel channel, ChannelHandler handler, ChannelState state, Throwable t) {
this(channel, handler, state, null, t);
}
public ChannelEventRunnable(Channel channel, ChannelHandler handler, ChannelState state, Object message, Throwable exception) {
this.channel = channel;
this.handler = handler;
this.state = state;
this.message = message;
this.exception = exception;
}
@Override
public void run() {
if (state == ChannelState.RECEIVED) {
try {
handler.received(channel, message);
} catch (Exception e) {
logger.warn("ChannelEventRunnable handle " + state + " operation error, channel is " + channel
+ ", message is " + message, e);
}
} else {
switch (state) {
case CONNECTED:
try {
handler.connected(channel);
} catch (Exception e) {
logger.warn("ChannelEventRunnable handle " + state + " operation error, channel is " + channel, e);
}
break;
case DISCONNECTED:
try {
handler.disconnected(channel);
} catch (Exception e) {
logger.warn("ChannelEventRunnable handle " + state + " operation error, channel is " + channel, e);
}
break;
case SENT:
try {
handler.sent(channel, message);
} catch (Exception e) {
logger.warn("ChannelEventRunnable handle " + state + " operation error, channel is " + channel
+ ", message is " + message, e);
}
break;
case CAUGHT:
try {
handler.caught(channel, exception);
} catch (Exception e) {
logger.warn("ChannelEventRunnable handle " + state + " operation error, channel is " + channel
+ ", message is: " + message + ", exception is " + exception, e);
}
break;
default:
logger.warn("unknown state: " + state + ", message is " + message);
}
}
}
/**
* ChannelState
*
*
*/
public enum ChannelState {
/**
* CONNECTED
*/
CONNECTED,
/**
* DISCONNECTED
*/
DISCONNECTED,
/**
* SENT
*/
SENT,
/**
* RECEIVED
*/
RECEIVED,
/**
* CAUGHT
*/
CAUGHT
}
}ChannelEventRunnable实现了Runnable接口，其run方法根据不同的ChannelState做不同处理
小结
WrappedChannelHandler的构造根据ExtensionLoader.getExtensionLoader(ThreadPool.class).getAdaptiveExtension().getExecutor(url)获取ExecutorService，然后放到dataStore中
ExecutionChannelHandler继承了WrappedChannelHandler，其received会创建ChannelEventRunnable，然后放到executor去执行
ChannelEventRunnable实现了Runnable接口，其run方法根据不同的ChannelState做不同处理
“dubbo的WrappedChannelHandler有什么作用”的内容就介绍到这里了，感谢大家的阅读。如果想了解更多行业相关的知识可以关注创新互联网站，小编将为大家输出更多高质量的实用文章！
名称栏目：dubbo的WrappedChannelHandler有什么作用
文章链接：http://scjbc.cn/article/gcjeec.html
