Socket简单用法

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。

• SocketServer类，服务器实现：

package HA.Socket;
 2 
 3 import java.io.*;
 4 import java.net.*;
 5 
 6  publicclass SocketServer {
 7     
 8     ServerSocket sever;
 9     
10 public SocketServer(int port){
11 try{
12             sever =new ServerSocket(port);
13         }catch(IOException e){
14             e.printStackTrace();
15         }
16     }
17     
18 publicvoid beginListen(){
19 while(true){
20 try{
21                 final Socket socket = sever.accept();
22                 
23 new Thread(new Runnable(){
24 publicvoid run(){
25                         BufferedReader in;
26 try{
27 in=new BufferedReader(new InputStreamReader(socket.getInputStream(),"UTF-8"));
28                             PrintWriter out=new PrintWriter(socket.getOutputStream());
29 while (!socket.isClosed()){
30                                 String str;
31                                 str =in.readLine();
32 out.println("Hello!world!! "+ str);
33 out.flush();
34 if (str ==null|| str.equals("end"))
35 break;
36                                 System.out.println(str);
37                             }
38                             socket.close();
39                         }catch(IOException e){
40                             e.printStackTrace();
41                         }
42                     }
43                 }).start();
44             }catch(IOException e){
45                 e.printStackTrace();
46             }
47         }
48     }
49 }

• SocketClient类，客户端实现：

package HA.Socket;
 2 
 3 import java.io.*;
 4 import java.net.*;
 5 
 6  publicclass SocketClient {
 7 static Socket client;
 8     
 9 public SocketClient(String site, int port){
10 try{
11             client =new Socket(site,port);
12             System.out.println("Client is created! site:"+site+" port:"+port);
13         }catch (UnknownHostException e){
14             e.printStackTrace();
15         }catch (IOException e){
16             e.printStackTrace();
17         }
18     }
19     
20 public String sendMsg(String msg){
21 try{
22             BufferedReader in=new BufferedReader(new InputStreamReader(client.getInputStream()));
23             PrintWriter out=new PrintWriter(client.getOutputStream());
24 out.println(msg);
25 out.flush();
26 returnin.readLine();
27         }catch(IOException e){
28             e.printStackTrace();
29         }
30 return"";
31     }
32 publicvoid closeSocket(){
33 try{
34             client.close();
35         }catch(IOException e){
36             e.printStackTrace();
37         }
38     }
39 publicstaticvoid main(String[] args) throws Exception{
40         
41     }
42 
43 }

    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！

package HA.Socket;
2 
3  publicclass TestSocketServer {
4     
5 publicstaticvoid main(String[] argvs){
6         SocketServer server =new SocketServer(12345);
7         server.beginListen();
8     }
9 }

   再运行TestSocketClient类：

package HA.Socket;
 2 
 3  publicclass TestSocketClient {
 4 
 5 publicstaticvoid main(String[] args){
 6         
 7         SocketClient client =new SocketClient("127.0.0.1",12345);
 8         System.out.println(client.sendMsg("nimei1"));
 9         client.closeSocket();
10         
11         SocketClient client1 =new SocketClient("127.0.0.1",12345);
12         System.out.println(client1.sendMsg("nimei1111"));
13         client1.closeSocket();
14         
15         SocketClient client11 =new SocketClient("127.0.0.1",12345);
16         System.out.println(client11.sendMsg("nimei11111111"));
17         client11.closeSocket();
18         
19         SocketClient client111 =new SocketClient("127.0.0.1",12345);
20         System.out.println(client111.sendMsg("nimei11111111111111111"));
21         client111.closeSocket();
22         
23     }
24 }

 输出结果如下：

服务端：

Client is created! site:127.0.0.1 port:12345
Hello!world!! nimei1
Client is created! site:127.0.0.1 port:12345
Hello!world!! nimei1111
Client is created! site:127.0.0.1 port:12345
Hello!world!! nimei11111111
Client is created! site:127.0.0.1 port:12345
Hello!world!! nimei11111111111111111

客户端：

nimei1
nimei1111
nimei11111111
nimei11111111111111111

标签: android