udpsocketsend.java

JAVA编程思想源代码 值得一下 很难找的

package chapter15;

import java.applet.Applet;
import java.awt.Button;
import java.awt.Graphics;
import java.awt.Label;
import java.awt.TextField;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.UnknownHostException;

public class UDPSocketSend extends Applet {
	TextField t;

	public void init() {

		Label label1 = new Label("发送的消息:");
		add(label1);
		t = new TextField(20);
		add(t);
		Button b = new Button("发送消息");
		mouseListener m = new mouseListener();
		b.addMouseListener(m); //为按钮添加鼠标事件
		add(b);
	}

	public void paint(Graphics g) {
	}

	class mouseListener implements MouseListener {

		public void mouseReleased(MouseEvent m) {
		}

		public void mouseClicked(MouseEvent m) {

			String host = "localhost";
			byte message[] = new byte[256];

			try {
				InetAddress addr = InetAddress.getByName(host); //获取本机地址
				message = t.getText().getBytes(); //获取用户指定的要发送的消息
				DatagramPacket packet = new DatagramPacket(message,
						message.length, addr, 3000);//创建数据报对象，指定目的地址和端口号
				DatagramSocket socket;

				try {
					socket = new DatagramSocket(); //创建DatagramSocket套接字对象
					socket.send(packet); //发送数据报
					t.setText(""); //清空消息输入框
					socket.close(); //关闭套接字
				} catch (Exception e) {
					e.printStackTrace();
				}
			} catch (UnknownHostException e) {
				e.printStackTrace();
			}
		}

		public void mouseEntered(MouseEvent m) {
		}

		public void mousePressed(MouseEvent m) {
		}

		public void mouseExited(MouseEvent m) {
		}
	}
}