DataGram客户端 - 服务器Java - 消息传输问题

Question

Hy，我必须做一个客户端 - 服务器DataGram通信，我有一个小问题。发送-recive方法工作良好，但如果我尝试从客户端发送谢胜利时，服务器将不recive再整个邮件：

Server Started and listening to the port 10000 
Recive from client: Send me a datagram 
Send to client: I am Server! 

Recive from client: Send me a da  -> HERE is the PROBLEM 
Send to client: I am Server! 

在TCP传输我kwnow，我要刷新缓冲区，但在DataGram中我需要做什么？

DGSServerT：

public class DGSServerT { 
    public static void main (String [] args) throws IOException { 
     final int port = 10000; 

     // Create a datagram socket bound to port 10000. Datagram packets sent from client programs arrive at this port. 
     DatagramSocket s = new DatagramSocket (port); 
     System.out.println("Server Started and listening to the port " + port); 

     // Create a byte array to hold data contents of datagram packet. 
     byte [] data = new byte [100]; 

     // Create a DatagramPacket object that encapsulates a reference to the byte array and destination address information. The 
     // DatagramPacket object is not initialized to an address because it obtains that address from the client program. 
     DatagramPacket dgp = new DatagramPacket (data, data.length); 

     // Enter an infinite loop. Press Ctrl+C to terminate program. 
     while (true) { 
      // Receive a datagram packet from the client program. 
      s.receive (dgp); 
      // Display contents of datagram packet. 
      System.out.println ("Recive from client: " + new String (data)); 

      InetAddress address = dgp.getAddress(); 
      int clPort = dgp.getPort(); 
      data = new String ("I am Server!").getBytes(); 
      dgp = new DatagramPacket (data, data.length, address, clPort); 

      // Echo datagram packet back to client program. 
      s.send (dgp); 
      System.out.println ("Send to client: " + new String (data)); 
     } 
    } 
} 

DGSClientT：

public class DGSClientT { 
    public static void main (String [] args) { 
     String host = "localhost"; 

     // If user specifies a command-line argument, that argument represents the host name. 
     if (args.length == 1) { 
      host = args [0]; 
     } 
     DatagramSocket s = null; 

     try { 
      s = new DatagramSocket(); 

      // Create a byte array that will hold the data portion of a datagram packet's message 
      byte [] buffer = new String ("Send me a datagram").getBytes(); 

      InetAddress ia = InetAddress.getByName (host); 
      DatagramPacket dgp = new DatagramPacket (buffer, buffer.length, ia, 10000); 

      // Send the datagram packet over the socket. 
      s.send (dgp); 
      System.out.println("Send to server: " + new String (dgp.getData())); 

      // Create a byte array to hold the response from the server program 
      byte [] buffer2 = new byte [100]; 

      // Create a DatagramPacket object that specifies a buffer to hold the server program's response, the IP address of 
      // the server program's computer, and port number 10000. 
      DatagramPacket dgp2 = new DatagramPacket (buffer2, buffer.length, ia, 10000); 

      // Receive a datagram packet over the socket. 
      s.receive (dgp2); 

      // Print the data returned from the server program and stored in the datagram packet. 
      System.out.println ("Recive from Server: " + new String (dgp2.getData())); 
     } catch (IOException e) { 
      System.out.println (e.toString()); 
     } finally { 
      if (s != null) { 
       s.close(); 
      } 
     } 
    } 
} 

Answer 1

你必须到第一线移动：

DatagramPacket dgp = new DatagramPacket (data, data.length); 

进 “而” 循环。在发送服务器答案时，在while循环结束时，“dgp”的缓冲区长度为12个字节。