一、类介绍
1.ChannelPool——连接池接口
2.SimpleChannelPool——实现ChannelPool接口，简单的连接池实现
3.FixedChannelPool——继承SimpleChannelPool，有大小限制的连接池实现
4.ChannelPoolMap——管理host与连接池映射的接口
5.AbstractChannelPoolMap——抽象类，实现ChannelPoolMap接口
二、具体使用
a、MyNettyPool——Netty自带连接池的用法
package com.dxfx.netty.demo;import com.alibaba.fastjson.JSONObject;import com.dxfx.netty.framework.Constants;import com.dxfx.netty.framework.DefaultFuture;import com.dxfx.netty.framework.NettyClientHandler;import com.dxfx.netty.param.RequestParam;import com.dxfx.netty.param.Response;import io.netty.bootstrap.Bootstrap;import io.netty.channel.Channel;import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.pool.AbstractChannelPoolMap;import io.netty.channel.pool.ChannelPoolHandler;import io.netty.channel.pool.ChannelPoolMap;import io.netty.channel.pool.FixedChannelPool;import io.netty.channel.socket.nio.NioSocketChannel;import io.netty.handler.codec.DelimiterBasedFrameDecoder;import io.netty.handler.codec.Delimiters;import io.netty.handler.codec.string.StringDecoder;import io.netty.handler.codec.string.StringEncoder;import io.netty.util.concurrent.Future;import io.netty.util.concurrent.FutureListener;/** * Netty自带连接池的用法 * ?* @author Administrator * */public class MyNettyPool { ???// key为目标host，value为目标host的连接池 ???public static ChannelPoolMap<String, FixedChannelPool> poolMap; ???private static final Bootstrap bootstrap = new Bootstrap(); ???static { ???????bootstrap.group(new NioEventLoopGroup()); ???????bootstrap.channel(NioSocketChannel.class); ???????bootstrap.remoteAddress("localhost", 8080); ???} ???public MyNettyPool() { ???????init(); ???} ???/** ????* netty连接池使用 ????* ?????*/ ???public void init() { ???????poolMap = new AbstractChannelPoolMap<String, FixedChannelPool>() { ???????????@Override ???????????protected FixedChannelPool newPool(String key) { ???????????????ChannelPoolHandler handler = new ChannelPoolHandler() { ???????????????????/** ????????????????????* 使用完channel需要释放才能放入连接池 ????????????????????* ?????????????????????*/ ???????????????????@Override ???????????????????public void channelReleased(Channel ch) throws Exception { ???????????????????????// 刷新管道里的数据 ???????????????????????// ch.writeAndFlush(Unpooled.EMPTY_BUFFER); // flush掉所有写回的数据 ?????????????????????????System.out.println("channelReleased......"); ???????????????????} ???????????????????/** ????????????????????* 当链接创建的时候添加channelhandler，只有当channel不足时会创建，但不会超过限制的最大channel数 ????????????????????* ?????????????????????*/ ???????????????????@Override ???????????????????public void channelCreated(Channel ch) throws Exception { ???????????????????????ch.pipeline().addLast(new StringEncoder()); ???????????????????????ch.pipeline().addLast(new DelimiterBasedFrameDecoder(Integer.MAX_VALUE, Delimiters.lineDelimiter()[0])); ???????????????????????ch.pipeline().addLast(new StringDecoder()); ????????????????????????// 绑定channel的handler ???????????????????????ch.pipeline().addLast(new NettyClientHandler()); ???????????????????} ???????????????????/** ????????????????????* ?获取连接池中的channel ????????????????????* ??????????????????????*/ ???????????????????@Override ???????????????????public void channelAcquired(Channel ch) throws Exception { ???????????????????????System.out.println("channelAcquired......"); ???????????????????} ???????????????}; ???????????????????????????????return new FixedChannelPool(bootstrap, handler, 50); //单个host连接池大小 ???????????} ???????}; ???} ???/** ????* 发送请求 ????* ?????* @param msg ????* ???????????请求参数 ????* @param command ????* ???????????请求方法 ????* @return ????*/ ???public Response send(final Object msg, final String command) { ???????//封装请求数据 ???????final RequestParam request = new RequestParam(); ???????request.setCommand(command); ???????request.setContent(msg); ???????????????//从连接池中获取连接 ???????final FixedChannelPool pool = poolMap.get("localhost"); ???????//申请连接，没有申请到或者网络断开，返回null ???????Future<Channel> future = pool.acquire(); ???????future.addListener(new FutureListener<Channel>() { ???????????@Override ???????????public void operationComplete(Future<Channel> future) throws Exception { ???????????????//给服务端发送数据 ???????????????Channel channel = future.getNow(); ???????????????channel.write(JSONObject.toJSONString(request)); ???????????????channel.writeAndFlush(Constants.DELIMITER); ???????????????System.out.println(channel.id()); ???????????????// 连接放回连接池，这里一定记得放回去 ???????????????pool.release(channel); ???????????} ???????}); ???????????????//获取服务端返回的数据 ???????DefaultFuture defaultFuture = new DefaultFuture(request); ???????return defaultFuture.get(); ???}}b、MyNettyPoolTest——Netty自带连接池测试类，SpringServer为连接池启动类
package com.dxfx.netty.demo;import com.dxfx.netty.param.Response;import com.dxfx.user.model.User;/** * Netty自带连接池测试类，SpringServer为连接池启动类 * ?* @author Administrator * */public class MyNettyPoolTest { ???public static void main(String[] args) { ???????User user = new User(); ???????user.setAge(12); ???????user.setId(23); ???????user.setName("client"); ???????String command = "login"; ???????????????MyNettyPool pool = new MyNettyPool(); ???????new MyThread(pool, user, command).start(); ???????new MyThread(pool, user, command).start(); ???????new MyThread(pool, user, command).start(); ???????new MyThread(pool, user, command).start(); ???????for (int i = 0; i < 50000; i++) { ???????????new MyThread(pool, user, command).start(); ???????} ???}}class MyThread extends Thread { ???public MyNettyPool pool; ???public Object msg; ???public String command; ???public MyThread(MyNettyPool pool, Object msg, String command) { ???????super(); ???????this.pool = pool; ???????this.msg = msg; ???????this.command = command; ???} ???@Override ???public void run() { ???????Response response = pool.send(msg, command); ???????//System.out.println(response); ???}}Netty自带连接池的使用
原文地址：https://www.cnblogs.com/linjiqin/p/10125507.html