JAVA NIO TCP SOCKET 聊天群发(并发多线程写消息篇)

服务器中转消息，是费时的事，可以加入多线程。这样以来，会产生很多线程。可以运用线程池来管理。
这里运用java.util.concurrent包的Executors.newCachedThreadPool来管理。
废话少说，上代码：
服务器端：MySocketServer.java
/*
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package com.kevin.nio;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.Date;
import java.util.Iterator;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
 *
 * @author kevin
 */
public class MySocketServer implements Runnable{
  
    private boolean running;
   
    private Selector selector;
    String writeMsg;
   
    SelectionKey ssckey;
    ExecutorService exec;
   
    public MySocketServer(){
       
        running=true;
        exec=Executors.newCachedThreadPool();
    }
   
    public void init(){
        try {
            selector = Selector.open();
            ServerSocketChannel ssc = ServerSocketChannel.open();
            ssc.configureBlocking(false);
            ssc.socket().bind(new InetSocketAddress(2345)