Socket简单用法

来源：互联网发布：编程教程视频编辑：程序博客网时间：2024/05/19 19:16

Socket通常也称做”套接字“，用于描述IP地址和端口，废话不多说，它就是网络通信过程中端点的抽象表示。值得一提的是，Java在包java.net中提供了两个类Socket和ServerSocket，分别用来表示双向连接的客户端和服务端。这是两个封装得非常好的类，使用起来很方便！

下面将首先创建一个SocketServer的类作为服务端如下，该服务端实现了多线程机制，可以在特定端口处监听多个客户请求，一旦有客户请求，Server总是会创建一个服务纯种来服务新来的客户，而自己继续监听。程序中accept()是一个阻塞函数，所谓阻塞性方法就是说该方法被调用后将等待客户的请求，直到有一个客户启动并请求连接到相同的端口，然后accept()返回一个对应于客户的Socket。这时，客户方和服务方都建立了用于通信的Socket，接下来就是由各个Socket分别打开各自的输入、输出流。

package com.wop.ddddddd;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class SocketServer {
   // SocketServer类，服务器实现：
   ServerSocket sever;

   public SocketServer(int port) {
       try {
           sever = new ServerSocket(port);
       } catch (IOException e) {
           e.printStackTrace();
       }
   }

   public void beginListen() {
       while (true) {
           try {
               final Socket socket = sever.accept();
               new Thread(new Runnable() {
                   public void run() {
                       BufferedReader in;
                       try {
                           in = new BufferedReader(new InputStreamReader(
                                   socket.getInputStream(), "UTF-8"));
                           PrintWriter out = new PrintWriter(
                                   socket.getOutputStream());
                           while (!socket.isClosed()) {
                               String str;
                               str = in.readLine();
                               out.println("Hello!world!! " + str);
                               out.flush();
                               if (str == null || str.equals("end"))
                                   break;
                               System.out.println(str);
                           }
                           socket.close();
                       } catch (IOException e) {
                           e.printStackTrace();
                       }
                   }
               }).start();
           } catch (IOException e) {
               e.printStackTrace();
           }
       }
   }
}

package com.wop.ddddddd;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;

public class SocketClient {
   static Socket client;

   // SocketClient类，客户端实现：
   public SocketClient(String site, int port) {
       try {
           client = new Socket(site, port);
           System.out.println("Client is created! site:" + site + " port:"
                   + port);
       } catch (UnknownHostException e) {
           e.printStackTrace();
       } catch (IOException e) {
           e.printStackTrace();
       }
   }

   public String sendMsg(String msg) {
       try {
           BufferedReader in = new BufferedReader(new InputStreamReader(
                   client.getInputStream()));
           PrintWriter out = new PrintWriter(client.getOutputStream());
           out.println(msg);
           out.flush();
           return in.readLine();
       } catch (IOException e) {
           e.printStackTrace();
       }
       return "";
   }

   public void closeSocket() {
       try {
           client.close();
       } catch (IOException e) {
           e.printStackTrace();
       }
   }

   public static void main(String[] args) throws Exception {

   }

}

package com.wop.ddddddd;

public class TestSocketClient {
   // 再运行TestSocketClient类：
   public static void main(String[] args) {
       SocketClient client = new SocketClient("127.0.0.1", 12345);
       System.out.println(client.sendMsg("nimei1"));
       client.closeSocket();
       SocketClient client1 = new SocketClient("127.0.0.1", 12345);
       System.out.println(client1.sendMsg("nimei1111"));
       client1.closeSocket();
       SocketClient client11 = new SocketClient("127.0.0.1", 12345);
       System.out.println(client11.sendMsg("nimei11111111"));
       client11.closeSocket();

       SocketClient client111 = new SocketClient("127.0.0.1", 12345);
       System.out.println(client111.sendMsg("nimei11111111111111111"));
       client111.closeSocket();
   }

}

package com.wop.ddddddd;

public class TestSocketServer {
   // 接下来就是来测试Socket通信了！
   // 先运行TestSocketServer类，打开服务端，在12345端口处监听！
   public static void main(String[] argvs) {
       SocketServer server = new SocketServer(12345);
       server.beginListen();
   }

}