Java-blog-09

Java-blog-09 一.仿照例15.4，编写基于TCP Socket的多客户/服务器通信程序

import java.io.*;
import java.net.*;
public class MultiTalkServer{
    static int clientnum=0; //静态成员变量，记录当前客户的个数
    public static void main(String args[]) throws IOException {
      ServerSocket serverSocket=null;
      boolean listening=true;
      try{
         //创建一个ServerSocket在端口4700监听客户请求
         serverSocket=new ServerSocket(4700); 
      }catch(IOException e) {
         System.out.println("Could not listen on port:4700.");
         System.exit(-1); //退出
      }
      while(listening){ //循环监听
      //监听到客户请求，根据得到的Socket对象和客户计数创建服务线程，并启动之
        new ServerThread(serverSocket.accept(),clientnum).start();
        clientnum++; //增加客户计数
      }
      serverSocket.close(); //关闭ServerSocket
  }
}

二.仿照例15.5，编写基于UDP数据报的多客户/服务器通信程序

（以下参照博客园）

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.io.BufferedReader;
import java.io.InputStreamReader;

public class QuoteClient {
    public static void main(String[] args) throws IOException {

        DatagramSocket socket=new DatagramSocket();//创建数据报套接字
        BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));
        String readLine;
        InetAddress address=InetAddress.getByName("127.0.0.1");//Server的IP信息
        while(!(readLine = sin.readLine()).equals("bye")) {
            byte[] buf = readLine.getBytes();
            //创建DatagramPacket对象
            DatagramPacket packet=new DatagramPacket(buf, buf.length, address, 4445);
            socket.send(packet); //发送
            buf = new byte[256];
            //创建新的DatagramPacket对象，用来接收数据报
            packet=new DatagramPacket(buf,buf.length);
            socket.receive(packet); //接收
            buf = packet.getData();
            //根据接收到的字节数组生成相应的字符串
            String received=new String(buf);
            //打印生成的字符串
            System.out.println("Quote of the Sever: "+received );
        }
        socket.close(); //关闭套接口
    }
}

public class QuoteServer {
    public static void main(String args[])throws java.io.IOException{
        new QuoteServerThread().start();// 启动一个QuoteServerThread线程
    }
}

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

public class QuoteServerThread extends Thread// 服务器线程
{
    protected DatagramSocket socket = null;// DatagramSocket
    protected BufferedReader in = null;// Reader
    protected boolean moreQuotes = true;// 标志变量。是否继续 *** 作

    public QuoteServerThread() throws IOException {//
        this("QuoteServerThread");// QuoteServerThread
    }

    public QuoteServerThread(String name) throws IOException {
        super(name); //
        socket = new DatagramSocket(4445);// 创建数据报套接字端口4445
        in = new BufferedReader(new InputStreamReader(System.in));
    }

    public void run() // 线程主体
    {
        while (moreQuotes) {
            try {
                byte[] buf = new byte[256]; // 创建缓冲区
                DatagramPacket packet = new DatagramPacket(buf, buf.length);
                // 由缓冲区构建DatagramPacket对象
                socket.receive(packet); // 接收数据报
                // 输出客户端发送的内容
                System.out.println(new String(packet.getData()));
                // 从屏幕获取输入内容，作为发送给客户端的内容
                String dString = in.readLine();
                // 如果是bey，则向客户端发完消息后退出
                if (dString.equals("bye")) {
                    moreQuotes = false;
                }
                buf = dString.getBytes();// 把String转换成字节数组，以便传送
                // 从Client端传来的Packet中得到Client地址
                InetAddress address = packet.getAddress();
                int port = packet.getPort(); // 端口号
                // 根据客户端信息构建DatagramPacket
                packet = new DatagramPacket(buf, buf.length, address, port);
                socket.send(packet); // 发送数据报
            } catch (IOException e) { // 异常处理
                e.printStackTrace(); // 输出异常栈信息
                moreQuotes = false; // 标志变量置false，以结束循环
            }
        }
        socket.close(); // 关闭数据报套接字
    }
}