Java开发练习9.1 网络编程UDP

1.使用UDP协议编写一个网络程序，设置接收端程序的监听端口是8001，发送端发送的数据是“Hello,world”

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

public class fashong {

	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		DatagramSocket ds = new DatagramSocket(3000);
		String str = "hollo world";
		DatagramPacket dp = new DatagramPacket(str.getBytes(), str.length(),InetAddress.getByName("localhost"),7788);
		ds.send(dp);
		ds.close();
	}

}

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

public class jieshou {

	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		byte[] buf = new byte[1024];
		DatagramSocket ds = new DatagramSocket(7788);
		//DatagramPacket(byte[] buf, int length) ：用于接收端，length是缓存区buf的长度
		 DatagramPacket dp = new DatagramPacket(buf, 1024);
		 ds.receive(dp); //该方法用于将数据填充到DatagramPacket中
		 dp.getData();//返回接受到的数据
		 String str = new String (dp.getData());
		 System.out.println(str);
		 ds.close();
	}

}