基于udp报的发送和接受，使用wireshark 进行检测

基于udp报的发送和接受，使用wireshark 进行检测

• java server代码

package udp;

import java.net.*;

class UDPServer
{
    public static void main(String args[]) throws Exception
    {
        DatagramSocket serverSocket = new DatagramSocket(8899);
        byte[] receiveData = new byte[1024];
        byte[] sendData = new byte[1024];
        while(true)
        {
            DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
            serverSocket.receive(receivePacket);
            String sentence = new String( receivePacket.getData());
            System.out.println("RECEIVED: " + sentence);
            InetAddress IPAddress = receivePacket.getAddress();
            int port = receivePacket.getPort();
            String capitalizedSentence = sentence.toUpperCase();
            sendData = capitalizedSentence.getBytes();
            DatagramPacket sendPacket =
                    new DatagramPacket(sendData, sendData.length, IPAddress, port);
            serverSocket.send(sendPacket);
        }
    }
}

• java client 代码

  package udp;
  
  import java.io.*;
  import java.net.*;
  
  class UDPClient {
      public static void main(String args[]) {
          DatagramSocket clientSocket = null;
          try {
              clientSocket = new DatagramSocket();
              while (true) {
                  BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
                  InetAddress IPAddress = InetAddress.getByName("localhost");
                  byte[] sendData = new byte[1024];
                  byte[] receiveData = new byte[1024];
                  String sentence = inFromUser.readLine();
                  sendData = sentence.getBytes();
                  DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 8899);
                  clientSocket.send(sendPacket);
                  DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
                  clientSocket.receive(receivePacket);
                  String modifiedSentence = new String(receivePacket.getData());
                  System.out.println("FROM SERVER:" + modifiedSentence);
              }
          } catch (SocketException e) {
              e.printStackTrace();
          } catch (UnknownHostException e) {
              e.printStackTrace();
          } catch (IOException e) {
              e.printStackTrace();
          } finally {
              clientSocket.close();
          }
  
      }
  }
  

步骤

• 1 先运行java server的代码
• 2 运行javaclient的代码
• 3 在client 的等待系统输入中输入 hello
• 4 server 接收到hello 并发送回client
• 5 使用wireShark 检测这个动作
• udp.port eq 8899
• ![1561341452203](assets/

  

  .png)