import java.awt.BorderLayout;

import java.awt.Container;

import java.awt.FlowLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.io.IOException;

import java.net.DatagramPacket;

import java.net.DatagramSocket;

import java.net.InetAddress;

import java.net.SocketException;

import java.net.UnknownHostException;



import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JPanel;

import javax.swing.JTextArea;

import javax.swing.JTextField;



public class Talk extends JFrame{
JLabel la=new JLabel("请输入");
JTextField tfd=new JTextField(20);
JButton but=new JButton("发送");
JPanel p=new JPanel();
JTextArea jta=new JTextArea(10,20);
Container c;
DatagramSocket ds;
DatagramReceive dc;
int localPost=3000;
int remotePost=5000;
boolean flag=true;
public void init(){
	c=this.getContentPane();
	c.setLayout(new BorderLayout());
	p.setLayout(new FlowLayout());
	p.add(la);p.add(tfd);p.add(but);
	c.add(p,BorderLayout.NORTH);
	c.add(jta,BorderLayout.CENTER);
	but.addActionListener(new ActionListener(){
		public void actionPerformed(ActionEvent e){
			String temp=tfd.getText();
			jta.append("\n我说："+temp);
			byte[] buf=temp.getBytes();
			try {
				DatagramPacket dp=new DatagramPacket(buf,buf.length,InetAddress.getByName("localhost"),remotePost);
				try {
					ds.send(dp);
				} catch (IOException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}
				if(temp.trim().equals("bye")){
					flag=false;
					//dc.close();
				}
			} catch (UnknownHostException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
			
		}
	});
this.setSize(500,500);
this.setVisible(true);
}
public Talk(String name,int localPost,int remotePost){
	super(name);
	this.localPost=localPost;
	this.remotePost=remotePost;
	init();
	try {
		ds=new DatagramSocket(localPost);
		dc=new DatagramReceive(name,ds,jta);
		dc.start();
	} catch (SocketException e) {
		// TODO Auto-generated catch block
		System.out.println("DatagramSocket创建失败");
	}
	
}
public static void main(String[] args) {
	Talk t1=new Talk("A",3000,5000);
	Talk t2=new Talk("B",5000,3000);
}



}

import java.io.IOException;

import java.net.DatagramPacket;

import java.net.DatagramSocket;



import javax.swing.JTextArea;



public class DatagramReceive extends Thread{
String name;
DatagramSocket ds;
JTextArea jta;
boolean flag=true;
public DatagramReceive(String name,DatagramSocket ds,JTextArea jta){
	this.name=name;
	this.ds=ds;
	this.jta=jta;
}
	public void run(){
		while(flag){
			byte[] buf=new byte[1024];
			DatagramPacket dp=new DatagramPacket(buf,buf.length);
			try {
				ds.receive(dp);
				String temp=new String(buf,0,dp.getLength());
				jta.append("\n对方说："+temp);
				if(temp.trim().equals("bye")){
					flag=false;
					ds.close();
				}
			} catch (IOException e) {
				// TODO Auto-generated catch block
				System.out.println(name+"接受失败");
			}
			
		}
	}



}