net.jahhan.extension.protocol.ReferenceCountExchangeClient Maven / Gradle / Ivy

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/*
 * Copyright 1999-2011 Alibaba Group.
 *  
 * 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.
 */
package net.jahhan.extension.protocol;

import java.net.InetSocketAddress;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicInteger;

import com.alibaba.dubbo.common.Constants;
import com.alibaba.dubbo.common.Parameters;
import com.alibaba.dubbo.common.URL;
import com.alibaba.dubbo.remoting.RemotingException;
import com.alibaba.dubbo.remoting.exchange.ExchangeClient;
import com.alibaba.dubbo.remoting.exchange.ExchangeHandler;
import com.alibaba.dubbo.remoting.exchange.ResponseFuture;

import net.jahhan.spi.ChannelHandler;

/**
 * dubbo protocol support class.
 * 
 * @author chao.liuc
 */
@SuppressWarnings("deprecation")
public final class ReferenceCountExchangeClient implements ExchangeClient {

	private ExchangeClient client;

	private final URL url;

	// private final ExchangeHandler handler;

	private final AtomicInteger refenceCount = new AtomicInteger(0);

	private final ConcurrentMap ghostClientMap;

	public ReferenceCountExchangeClient(ExchangeClient client,
			ConcurrentMap ghostClientMap) {
		this.client = client;
		refenceCount.incrementAndGet();
		this.url = client.getUrl();
		if (ghostClientMap == null) {
			throw new IllegalStateException("ghostClientMap can not be null, url: " + url);
		}
		this.ghostClientMap = ghostClientMap;
	}

	public void reset(URL url) {
		client.reset(url);
	}

	public ResponseFuture request(Object request) throws RemotingException {
		return client.request(request);
	}

	public URL getUrl() {
		return client.getUrl();
	}

	public InetSocketAddress getRemoteAddress() {
		return client.getRemoteAddress();
	}

	public ChannelHandler getChannelHandler() {
		return client.getChannelHandler();
	}

	public ResponseFuture request(Object request, int timeout) throws RemotingException {
		return client.request(request, timeout);
	}

	public boolean isConnected() {
		return client.isConnected();
	}

	public void reconnect() throws RemotingException {
		client.reconnect();
	}

	public InetSocketAddress getLocalAddress() {
		return client.getLocalAddress();
	}

	public boolean hasAttribute(String key) {
		return client.hasAttribute(key);
	}

	public void reset(Parameters parameters) {
		client.reset(parameters);
	}

	public void send(Object message) throws RemotingException {
		client.send(message);
	}

	public ExchangeHandler getExchangeHandler() {
		return client.getExchangeHandler();
	}

	public Object getAttribute(String key) {
		return client.getAttribute(key);
	}

	public void send(Object message, boolean sent) throws RemotingException {
		client.send(message, sent);
	}

	public void setAttribute(String key, Object value) {
		client.setAttribute(key, value);
	}

	public void removeAttribute(String key) {
		client.removeAttribute(key);
	}

	/*
	 * close方法将不再幂等,调用需要注意.
	 */
	public void close() {
		close(0);
	}

	public void close(int timeout) {
		if (refenceCount.decrementAndGet() <= 0) {
			if (timeout == 0) {
				client.close();
			} else {
				client.close(timeout);
			}
			client = replaceWithLazyClient();
		}
	}

	// 幽灵client,
	private LazyConnectExchangeClient replaceWithLazyClient() {
		// 这个操作只为了防止程序bug错误关闭client做的防御措施，初始client必须为false状态
		URL lazyUrl = url.addParameter(Constants.LAZY_CONNECT_INITIAL_STATE_KEY, Boolean.FALSE)
				.addParameter(Constants.RECONNECT_KEY, Boolean.FALSE)
				.addParameter(Constants.SEND_RECONNECT_KEY, Boolean.TRUE.toString())
				.addParameter("warning", Boolean.TRUE.toString())
				.addParameter(LazyConnectExchangeClient.REQUEST_WITH_WARNING_KEY, true)
				.addParameter("_client_memo", "referencecounthandler.replacewithlazyclient");

		String key = url.getAddress();
		// 最差情况下只有一个幽灵连接
		LazyConnectExchangeClient gclient = ghostClientMap.get(key);
		if (gclient == null || gclient.isClosed()) {
			gclient = new LazyConnectExchangeClient(lazyUrl, client.getExchangeHandler());
			ghostClientMap.put(key, gclient);
		}
		return gclient;
	}

	public boolean isClosed() {
		return client.isClosed();
	}

	public void incrementAndGetCount() {
		refenceCount.incrementAndGet();
	}

	public void startClose() {
		client.startClose();
	}
}