Java网络聊天程序

UDP:
1、指定socket端口
2、在发送的包中指定发送到的地址和端口
3、发送的包中的端口必须和接受端的socket端口相同
java网络编程UDP
IO流，字符字节流转换，输入流
多线程

package UdpTest;

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

public class TalkReceive implements Runnable {

  private DatagramSocket server;

  public TalkReceive(int port) {
    try {
      this.server = new DatagramSocket(port);
    } catch (SocketException e) {
      e.printStackTrace();
    }
  }

  @Override
  public void run() {
    while (true) {
      byte[] container = new byte[1024 * 60]; // 60k
      DatagramPacket packet = new DatagramPacket(container, container.length);
      // 4、阻塞式接收包裹receive(DatagramSocket p)
      try {
        server.receive(packet);
        // 5、分析数据
        //    byte[] getData()
        //    getLength()
        byte[] datas = packet.getData();
        int len = packet.getLength();
        String msg = new String(datas, 0, len); // 制定长度，必须，否则默认按字节数组长度，equal比较会报错，我日
        if (msg.equals("exit")) {
          break;
        }
        System.out.println("对方说:" + msg);
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
    // 6、释放资源
    server.close();
  }
}

package UdpTest;

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 reader;
  private String toIP;
  private int toPort;

  public TalkSend(int port, String toIp, int toPort) {
    this.toIP = toIp;
    this.toPort = toPort;
    try {
      this.client = new DatagramSocket(port);
      this.reader = new BufferedReader(new InputStreamReader(System.in));
    } catch (SocketException e) {
      e.printStackTrace();
    }
  }

  @Override
  public void run() {
    while (true) {
      String msg = null;
      try {
        msg = this.reader.readLine();
        byte[] datas = msg.getBytes();
        // 3、封装成DatagramSocket包裹，需要指定目的地
        DatagramPacket packet = new DatagramPacket(datas, datas.length,
            new InetSocketAddress(this.toIP,
                this.toPort));
        // 4、发送接收包裹receive(DatagramSocket p)
        this.client.send(packet);
        if (msg.equals("exit")) {
          break;
        }
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
    client.close();
  }
}

package UdpTest;

public class TalkStudent {

  public static void main(String[] args) {
    new Thread(new TalkSend(7777, "localhost", 9999)).start(); //发送

    new Thread(new TalkReceive(8888)).start(); // 接收
  }
}

package UdpTest;

public class TalkTeacher {

  public static void main(String[] args) {
    new Thread(new TalkReceive(9999)).start(); // 接收

    new Thread(new TalkSend(5555, "localhost", 8888)).start(); //发送
  }
}