org.apache.dubbo.config.DubboShutdownHook Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
package org.apache.dubbo.config;
import org.apache.dubbo.common.extension.ExtensionLoader;
import org.apache.dubbo.common.lang.ShutdownHookCallbacks;
import org.apache.dubbo.common.logger.Logger;
import org.apache.dubbo.common.logger.LoggerFactory;
import org.apache.dubbo.config.event.DubboServiceDestroyedEvent;
import org.apache.dubbo.config.event.DubboShutdownHookRegisteredEvent;
import org.apache.dubbo.config.event.DubboShutdownHookUnregisteredEvent;
import org.apache.dubbo.event.Event;
import org.apache.dubbo.event.EventDispatcher;
import org.apache.dubbo.registry.support.AbstractRegistryFactory;
import org.apache.dubbo.rpc.Protocol;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* The shutdown hook thread to do the clean up stuff.
* This is a singleton in order to ensure there is only one shutdown hook registered.
* to store the shutdown hooks.
*/
public class DubboShutdownHook extends Thread {
private static final Logger logger = LoggerFactory.getLogger(DubboShutdownHook.class);
private static final DubboShutdownHook DUBBO_SHUTDOWN_HOOK = new DubboShutdownHook("DubboShutdownHook");
private final ShutdownHookCallbacks callbacks = ShutdownHookCallbacks.INSTANCE;
/**
* Has it already been registered or not?
*/
private final AtomicBoolean registered = new AtomicBoolean(false);
/**
* Has it already been destroyed or not?
*/
private final AtomicBoolean destroyed = new AtomicBoolean(false);
private final EventDispatcher eventDispatcher = EventDispatcher.getDefaultExtension();
private DubboShutdownHook(String name) {
super(name);
}
public static DubboShutdownHook getDubboShutdownHook() {
return DUBBO_SHUTDOWN_HOOK;
}
@Override
public void run() {
if (logger.isInfoEnabled()) {
logger.info("Run shutdown hook now.");
}
callback();
doDestroy();
}
/**
* For testing purpose
*/
void clear() {
callbacks.clear();
}
private void callback() {
callbacks.callback();
}
/**
* Register the ShutdownHook
*/
public void register() {
if (registered.compareAndSet(false, true)) {
destroyed.set(false);
DubboShutdownHook dubboShutdownHook = getDubboShutdownHook();
Runtime.getRuntime().addShutdownHook(dubboShutdownHook);
dispatch(new DubboShutdownHookRegisteredEvent(dubboShutdownHook));
}
}
/**
* Unregister the ShutdownHook
*/
public void unregister() {
if (registered.compareAndSet(true, false)) {
DubboShutdownHook dubboShutdownHook = getDubboShutdownHook();
Runtime.getRuntime().removeShutdownHook(dubboShutdownHook);
dispatch(new DubboShutdownHookUnregisteredEvent(dubboShutdownHook));
}
}
/**
* Destroy all the resources, including registries and protocols.
*/
public void doDestroy() {
// dispatch the DubboDestroyedEvent @since 2.7.5
dispatch(new DubboServiceDestroyedEvent(this));
if (destroyed.compareAndSet(false, true)) {
AbstractRegistryFactory.destroyAll();
destroyProtocols();
}
}
private void dispatch(Event event) {
eventDispatcher.dispatch(event);
}
public boolean getRegistered() {
return registered.get();
}
public static void destroyAll() {
getDubboShutdownHook().doDestroy();
}
/**
* Destroy all the protocols.
*/
public static void destroyProtocols() {
ExtensionLoader loader = ExtensionLoader.getExtensionLoader(Protocol.class);
for (String protocolName : loader.getLoadedExtensions()) {
try {
Protocol protocol = loader.getLoadedExtension(protocolName);
if (protocol != null) {
protocol.destroy();
}
} catch (Throwable t) {
logger.warn(t.getMessage(), t);
}
}
}
public static void reset() {
getDubboShutdownHook().destroyed.set(false);
getDubboShutdownHook().unregister();
}
}