Thread類實現多個客戶端連接服務端

利用Java的Thread類，實現多個客戶端同時連接服務端。
客戶端：

/**
 * Created by hades on 2017/3/16.
 */

import java.io.*;
import java.net.Socket;

public class EchoClient {
    private String host = "localhost";
    private int port = 8000;
    private Socket socket;

    public EchoClient() throws IOException {
        socket = new Socket(host, port);   //建立socket對象，用於與服務器的通信，需要綁定服務器端口。
    }

    private PrintWriter getWriter(Socket socket) throws IOException {  //輸出流
        OutputStream socketOut = socket.getOutputStream();
        return new PrintWriter(socketOut, true);
    }

    private BufferedReader getReader(Socket socket) throws IOException {  //輸入流
        InputStream socketIn = socket.getInputStream();
        return new BufferedReader(new InputStreamReader(socketIn));
    }

    public void talk() throws IOException {
        try {
            BufferedReader br = getReader(socket);
            PrintWriter pw = getWriter(socket);
            BufferedReader localReader = new BufferedReader(new InputStreamReader(System.in));
            String msg = null;
            while ((msg = localReader.readLine()) != null) {
                pw.println(msg);
                System.out.println(br.readLine());

                if(msg.equals("bye"))
                    break;
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String args[]) throws IOException {
        new EchoClient().talk();
    }
}

服務端：

/**
 * Created by hades on 2017/3/16.
 */

import java.io.*;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

public class EchoServer {
    private int port=8000;   //定義服務器連接端口
    private ServerSocket serverSocket;

    public EchoServer() throws IOException {
        serverSocket = new ServerSocket(port);  //新建serverSocket對象，綁定連接端口port
        System.out.println("服務器啓動...");
    }

    public String echo(String msg) {
        return "echo:" + msg;
    }
    public void service() throws IOException {
        Socket socket=null;
        try {
            int count = 0;
            while(true){
                socket=serverSocket.accept();
                //創建一個新的線程
                ServerThread serverThread=new ServerThread(socket,count);
                //啓動線程
                serverThread.start();

                count++;
                System.out.println("客戶端" + count + "已連接");
                System.out.println("當前客戶端的IP：" + socket.getInetAddress() + ":"  + socket.getPort());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            try{
                if(socket!=null)
                    socket.close();  //斷開連接
            }catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String args[]) throws IOException {
        new EchoServer().service();
    }
}

多線程：

/**
 * Created by hades on 2017/3/17.
 */

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;

public class ServerThread extends Thread{
    Socket socket = null;

    public ServerThread(Socket socket,int count) {

        this.socket = socket;
    }
    public String echo(String msg) {

        return "從服務端返回的消息:" + msg;
    }

    private PrintWriter getWriter(Socket socket) throws IOException {  //輸出流的建立
        OutputStream socketOut = socket.getOutputStream();
        return new PrintWriter(socketOut, true);
    }

    private BufferedReader getReader(Socket socket) throws IOException {  //輸入流的建立
        InputStream socketIn = socket.getInputStream();
        return new BufferedReader(new InputStreamReader(socketIn));
    }

    public  void run(){
        try {
            BufferedReader br =getReader(socket);
            PrintWriter pw = getWriter(socket);

            String msg = null;
            while ((msg = br.readLine()) != null) {
                System.out.println(msg);
                pw.println(echo(msg));
                if (msg.equals("bye")) //如果客戶發送的消息爲“bye”，就結束通信
                    break;
            }
        }catch (IOException e) {
            e.printStackTrace();
        }finally {
            try{
                if(socket!=null)socket.close();  //斷開連接
            }catch (IOException e) {e.printStackTrace();}
        }
    }
}