Java網絡編程入門——基於UDP協議實現最簡單的雙方通信（內核代碼）

前言

假設模擬學生端與教師端的聊天內容，在控制檯輸入聊天內容，按下回車鍵即可發送。代碼放在了GitHub上：https://github.com/MarsOu1998/LiveChat-CoreCode

效果

教師端：

學生端：

代碼

一共有4個java代碼，運行的時候記得運行TalkStudent.java和TeacherStudent.java

TalkReceive.java:

package main;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

public class TalkReceive implements Runnable {
    private DatagramSocket server;
    private int port;

    public TalkReceive(int port) throws SocketException {
        this.port = port;
        server=new DatagramSocket(port);
    }

    public void run() {
        while(true){
            byte[] contianer=new byte[1024*64];
            DatagramPacket packet=new DatagramPacket(contianer,0,contianer.length);
            try {
                server.receive(packet);
                byte[] datas=packet.getData();
                System.out.println("Ta:"+new String(datas, 0, packet.getLength()));
                if(datas.equals("bye")){
                    break;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        server.close();

    }
}

TalkSend.java:

package main;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketException;

public class TalkSend implements Runnable {
    private DatagramSocket client;
    private BufferedReader bufferedReader;
    private String toIP;
    private int toPort;
    public TalkSend(int port,String toIP,int toPort) throws SocketException {
        this.toIP=toIP;
        this.toPort=toPort;
        client=new DatagramSocket(port);
        bufferedReader=new BufferedReader(new InputStreamReader(System.in));
    }

    public void run() {
      while(true){
          String data;
          try {
              data=bufferedReader.readLine();
              byte[] datas=data.getBytes();
              DatagramPacket packet=new DatagramPacket(datas,0,datas.length,
                      new InetSocketAddress(toIP,toPort));
              client.send(packet);
              if(datas.equals("bye")){
                  break;
              }

          } catch (IOException e) {
              e.printStackTrace();
          }
      }
        client.close();
    }
}

talkStudent.java:

package main;

import java.net.SocketException;

public class talkStudent {
    public static void main(String[] args) throws SocketException {
        System.out.println("Student");
        new Thread(new TalkSend(7777,"127.0.0.1",9999)).start();
        new Thread(new TalkReceive(8888)).start();
    }
}

talkTeacher.java:

package main;

import java.net.SocketException;

public class talkTeacher {
    public static void main(String[] args) throws SocketException {
        System.out.println("Teacher");
        new Thread(new TalkReceive(9999)).start();
        new Thread(new TalkSend(6666,"127.0.0.1",8888)).start();
    }
}

結語

使用Java網絡編程實現最簡單的在線聊天，雙方通信的內核代碼，十分精簡，可擴展性強，適合嵌入您的項目，也可以獨立使用。核心技術爲多線程、數據包的收發、套接字。
如有問題，請給我留言，代碼可以在GitHub上下載和查看。