利用java UDP协议，实现简单的双人聊天

大概思路就是在主线程中，跑两个子线程，一个用于发送消息，另一个用于接收消息，就这么简单... =  =  代码附下：

/*	by wbin  2015/12/18

利用UDP协议，实现了简单的双人聊天	*/

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.util.Scanner;

public class Test {
	public static void main(String args[]){
		
		//send
		new Thread(new Runnable(){
			@Override
			public void run() {
				// TODO Auto-generated method stub
				SendSocket sendRun=new SendSocket();
				Thread sendThread=new Thread(sendRun);
				sendThread.start();
			}
		}).start();
		
		//receive
		new Thread(new Runnable(){
			@Override
			public void run() {
				// TODO Auto-generated method stub
				ReceiveSocket receiveRun = new ReceiveSocket();
				Thread receiveThread = new Thread(receiveRun);
				receiveThread.start();
			}
		}).start();
	}

	
	public static class SendSocket implements Runnable{
		@Override
		public void run() {
			// TODO Auto-generated method stub
			Scanner cin=new Scanner(System.in);
			DatagramSocket sendSocket=null;
			DatagramPacket packet=null;
			while(cin.hasNext()){	
				try {
				//	System.out.println("↑↑↑↑send:");	//System.out.println();
					byte[] b = cin.next().getBytes("utf-8");						//接收方的端口9387
					packet = new DatagramPacket(b, b.length, InetAddress.getByName("*.*.*.*"), 9387);	//接收方IP地址
					sendSocket = new DatagramSocket(9303);
					sendSocket.send(packet);
					sendSocket.close();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} 
			}
			if (cin != null)
				cin.close();
			if (sendSocket != null)
				sendSocket.close();
		}
	}

	public static class ReceiveSocket implements Runnable{
		@Override
		public void run() {
			// TODO Auto-generated method stub
			while(true){
				byte[] b = new byte[1024];
				DatagramPacket packet = new DatagramPacket(b, b.length);
				DatagramSocket receiveSocket = null;
				try {
					receiveSocket = new DatagramSocket(9367);	//监听9367端口
					receiveSocket.receive(packet);
					String text = new String(packet.getData(), 0, packet.getLength(),"utf-8");
					System.out.println("receive from "+packet.getAddress()+ ": " + text);
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} finally {
					receiveSocket.close();
				}
			}
		}   
	}
}
	

具体操作：比如A,B两个人，都是这份代码，要改的就是A的发送端口要与B的接收端口一致，A的接收端口要与B的发送端口一致，还有就是IP要对上咯..