android-->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;  import java.io.*; import java.net.*;   public class SocketServer {          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();             }         }     } }

   
• SocketClient类，客户端实现：

• package HA.Socket;  import java.io.*; import java.net.*;   public class SocketClient {     static Socket client;          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{              }  }

  
  接下来就是来测试Socket通信了！

• package HA.Socket;   public class TestSocketServer {          public static void main(String[] argvs){         SocketServer server = new SocketServer(12345);         server.beginListen();     } }

  
   
• 再运行TestSocketClient类：

• package HA.Socket;   public class TestSocketClient {      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();              } }

  
  
• 输出如下
• 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：

  nimei1nimei1111nimei11111111nimei11111111111111