1.客户端

package Thread;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;

public class Click {

    public static void main(String[] args) throws UnknownHostException, IOException {

        Click click=new Click();
        click.start();
    }

    private Socket socket;
    public Click() throws UnknownHostException, IOException {
        socket=new Socket("localhost", 8088);//连接指定的地址和端口

    }

    public void start() throws IOException {
        System.out.println("欢迎你,"+socket.getInetAddress());
        PrintWriter pw=null;
        //创建一条线程读取 服务器端发送过来的信息。
        Thread t=new Thread(new ServerHandler());
        t.setDaemon(true);//守护线程
        t.start();

        try {
            // 输出流,将客户端的消息发送出去
             pw=new PrintWriter(new OutputStreamWriter(socket.getOutputStream(),"utf-8"),true);

             Scanner scan=new Scanner(System.in);
             while(true){
                    pw.println(scan.nextLine());
                    }

        } catch (UnsupportedEncodingException e) {
            System.out.println("io流异常");
        } finally {
            if(socket!=null) {
                socket.close();
            }
        }
    }

    //读取服务端发送的消息
    class ServerHandler implements Runnable{

        public void run() {
            BufferedReader br=null;
            try {
                br=new BufferedReader(new InputStreamReader(socket.getInputStream(), "utf-8"));
                System.out.println(br.readLine());

            } catch (IOException e) {
                System.out.println("IOException");
            }
        }
    }
}

2.服务端

package Thread;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Server {

    public static void main(String[] args) throws IOException {
        Server server=new Server();
        server.start();
    }

    //成员变量
    private ExecutorService threadPool;
    private ServerSocket serverSocket;
    private List<PrintWriter>allOut;

    public Server() throws IOException {//初始化变量
        serverSocket=new ServerSocket(8088);
        threadPool=Executors.newFixedThreadPool(3);
        allOut=new ArrayList<PrintWriter>();
    }

    public void start() {

        try {
            while(true) {
                System.out.println("等待客户端连接");
            Socket socket=serverSocket.accept();//监听客户端的连接
            //每连接一条线程
            threadPool.execute(new ClickHandler(socket));
            }
        } catch (IOException e) {
            System.out.println("socket Exection");
        }
    }

    class ClickHandler implements Runnable{
        private Socket socket;
        public ClickHandler(Socket socket) {
            this.socket=socket;
        }
        //线程同步
        public synchronized void addOut(PrintWriter pw) {
            allOut.add(pw);
        }
        public synchronized void pwClose(PrintWriter pw) {
            pw.close();
        }

        public void run() {

            BufferedReader br;
            PrintWriter pw=null;
            try {
                System.out.println(socket.getInetAddress()+"连接成功");
                br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "utf-8"));
                //使用输出流将信息发到客户端
                 pw=new PrintWriter(new OutputStreamWriter(socket.getOutputStream(),"utf-8"), true);
                addOut(pw);
                String message=null;
                while((message=br.readLine())!=null) {
                        for(PrintWriter p:allOut) {
                            if(p!=pw) {
                                p.println(socket.getInetAddress()+":"+message);
                            }
                        }
                }
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } finally {
                pwClose(pw);
                if(socket!=null) {
                    try {
                        socket.close();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }

        }
    }

}

end

05-28 13:44