多线程-在线咨询 即使发送方，又是接收方-2022-12-20

发送方，接收方

package Chat;

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

public class Talksend implements Runnable{

    DatagramSocket socket = null;
    BufferedReader reader = null;

    private int fromPort;
    private String toIP;
    private int toPort;

    public Talksend(int fromPort, String toIP, int toPort) {
        this.fromPort = fromPort;
        this.toIP = toIP;
        this.toPort = toPort;
        try{
            socket = new DatagramSocket(fromPort);
            reader = new BufferedReader(new InputStreamReader(System.in));
        }catch (Exception e){
            e.printStackTrace();
        }
    }



    @Override
    public void run() {

        //准备数据，控制台读取数据 system.in

        while (true) {
            try{
                String data = reader.readLine();
                byte[] datas = data.getBytes();
                DatagramPacket packet = new DatagramPacket(datas, 0, datas.length, new InetSocketAddress(this.toIP,this.toPort));
                socket.send(packet);
                if (data.equals("bye")){
                    break;
                }
            }
            catch (Exception e){
                e.printStackTrace();
            }
        }

        socket.close();

    }
}

接收类

package Chat;

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

public class TalkReceive implements Runnable{
    DatagramSocket socket = null;
    private int port;
    private String MsgFrom;

    public TalkReceive(int port,String msgFrom) {
        this.port = port;
        this.MsgFrom = msgFrom;
        try {
            socket = new DatagramSocket(port);
        } catch (SocketException e) {
            throw new RuntimeException(e);
        }
    }


    @Override
    public void run() {

        while (true){
            try {
                byte[] container = new byte[10];
                DatagramPacket packet = new DatagramPacket(container,0,container.length);
                socket.receive(packet);

                byte[] data =packet.getData();
                String receivedata = new String(data, 0, data.length);
                System.out.println(MsgFrom+": "+receivedata);

                if (receivedata.equals("bye")){
                    break;
                }
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        socket.close();

    }
}
学生发消息，两个线程

package Chat;

public class TalkStudent {
    public static void main(String[] args) {
        //开启两个线程
        new Thread(new Talksend(7777,"localhost",9911)).start();
        new Thread(new TalkReceive(8822,"老师")).start();
    }
}

老师发消息，两个线程

package Chat;

public class TalkTeacher {
    public static void main(String[] args) {
        new Thread(new Talksend(5555,"localhost",8822)).start();
        new Thread(new TalkReceive(9911,"学生")).start();
    }
}