chat.java

聊天环境

import java.awt.*;
import java.awt.event.*;
import java.net.*;

public class Chat 
{
	Frame f=new Frame("电子科技大学聊天室");
	TextField tfIP=new TextField(15);
	List lst=new List(6);

	DatagramSocket ds;

	public Chat()
	{
		try
		{
			ds=new DatagramSocket(3000);
		}
		catch(Exception ex)
		{
			ex.printStackTrace();
		}
		new Thread(new Runnable()
		{
			public void run()
			{
				byte buf[]=new byte[1024];
				DatagramPacket dp=new DatagramPacket(buf,1024);
				while(true)
				{
					try
					{
						ds.receive(dp);
						lst.add(new String(buf,0,dp.getLength())+":from"+dp.getAddress().getHostAddress(),0);
					}
					catch(Exception e)
					{
						e.printStackTrace();
					}
				}
			}
		}).start();
	
	}

	public static void main(String args[])
	{
		Chat chat=new Chat();
		chat.init();
	}
	public void init()
	{
		f.setSize(300,300);
		f.add(lst);

		Panel p=new Panel();
		p.setLayout(new BorderLayout());
		p.add("West",tfIP);
		TextField tfData=new TextField(20);
		p.add("East",tfData);
		f.add("South",p);

		f.setVisible(true);
		f.setResizable(false);

		f.addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent e)
			{
				ds.close();
				f.setVisible(false);
				f.dispose();
				System.exit(0);
			}
		});

		tfData.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				byte[] buf;
				buf=e.getActionCommand().getBytes();
             try
				{
				DatagramPacket dp=new DatagramPacket(buf,buf.length,InetAddress.getByName(tfIP.getText()),3000);
				
					ds.send(dp);
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}
				((TextField)e.getSource()).setText("");
			}
		});
	}
}