package com.yjl.web.udp.talk;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketException;
/**
 * package: com.yjl.web.udp.talk
 * className: Send
 * Description: 请输入相应的描述
 *
 * @author : yuezl
 * @Date :2020/6/23 7:54
 */
public class Send implements  Runnable {
    /**
     * @param datagramSocket 客户端
     * @param port 客户端端口
     * @param from 客户端昵称
     * @param inetSocketAddress 指出服务器端
     */
    private DatagramSocket datagramSocket;
    private String from;
    private InetSocketAddress inetSocketAddress;
    //客户端是发送者
    public Send(int port, String from, InetSocketAddress inetSocketAddress){
        try {
            this.datagramSocket=new DatagramSocket(port);
        } catch (SocketException e) {
            e.printStackTrace();
        }
        this.from=from;
        this.inetSocketAddress=inetSocketAddress;
    }
    @Override
    public void run() {
        //接收控制台
        BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(System.in));
        if(from.indexOf("教师")<0){
            System.out.println(from+",请输入您的问题 ");
        }
        while(true){
            String content= null;
            try {
                //控制台输入的内容
                content = bufferedReader.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            byte[] bytes= new byte[0];
            try {
                bytes = content.getBytes("UTF-8");
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
            //4. 封装进包
            DatagramPacket datagramPacket=new DatagramPacket(bytes,0,bytes.length,this.inetSocketAddress);
            try {
                datagramSocket.send(datagramPacket);
            } catch (IOException e) {
                e.printStackTrace();
            }
            //如果输入 bye, 就关闭连接
            if("bye".equalsIgnoreCase(content)||"quit".equalsIgnoreCase(content)){
                System.out.println(from+"关闭了会话联系");
                break;
            }
        }
        //关闭流
        datagramSocket.close();
    }
}

package com.yjl.web.udp.talk;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
/**
 * package: com.yjl.web.udp.talk
 * className: Receiver
 * Description: 请输入相应的描述
 *
 * @author : yuezl
 * @Date :2020/6/23 7:54
 */
public class Receiver implements  Runnable {
    /**
     * @param from 服务器端昵称
     * @param port 服务器端接口
     */
    private DatagramSocket datagramSocket;
    private String from;
    public Receiver(int port,String from){
        try {
            this.datagramSocket=new DatagramSocket(port);
        } catch (SocketException e) {
            e.printStackTrace();
        }
        this.from=from;
    }
    @Override
    public void run() {
        byte[] bytes=new byte[1024];
        while(true){
            //能接收的大小，并不是实际接收的大小
            DatagramPacket datagramPacket=new DatagramPacket(bytes,0,bytes.length);
            //3. 阻塞式接收传递过来的数据
            try {
                datagramSocket.receive(datagramPacket);
            } catch (IOException e) {
                e.printStackTrace();
            }
            //4. 获取接收的数据
            byte[] content=datagramPacket.getData();
            int len=datagramPacket.getLength();
            String temp=new String(content,0,len);
            if("bye".equalsIgnoreCase(temp)||"quit".equalsIgnoreCase(temp)){
                System.out.println(from+"主动关闭了会话连接，退出了咨询室");
                break;
            }
            //输出内容
            System.out.println(from+":"+temp);
        }
        datagramSocket.close();
    }
}

public class StudentTalk {
    public static void main(String[] args) {
        //学生接收者， 接收者的昵称为教师
        new Thread(new Receiver(7777,"教师")).start();
        //发送者， 发送人是 学生1
        new Thread(new Send(8888,"学生1",new InetSocketAddress("localhost",9999))).start();
    }
}

public class TeacherTalk {
    public static void main(String[] args) {
        //接收者
        new Thread(new Receiver(9999,"学生1")).start();
        //发送者
        new Thread(new Send(6666,"教师",new InetSocketAddress("localhost",7777))).start();
    }
}