Java--UDP,接收方接收发送方的数据（单向）

Send(发送方):

 

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.DatagramPacket;

import java.net.DatagramSocket;

import java.net.InetAddress;

import java.net.SocketException;



public class SendDemo1 {



	private static final int PORT = 8080;

	private static final String IP = "localhost";

	public static void main(String[] args) {

		sendHandler();

	}



	private static void sendHandler(){

		DatagramSocket sendSocket = null;

		try {

			while(true){

				//创建套接字

				sendSocket = new DatagramSocket();

				//键盘录入

				BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

				String send = br.readLine();

				byte[] buf = send.getBytes();

				//设定数据包内容，长度，发送到的地址和端口

				DatagramPacket dp = new DatagramPacket(buf, buf.length, InetAddress.getByName(IP), PORT);

				//发送数据包

				sendSocket.send(dp);

			}

		} catch (SocketException e) {

			e.printStackTrace();

		} catch (IOException e) {

			e.printStackTrace();

		}finally{

			if(sendSocket != null){

				sendSocket.close();

			}

		}

	}

}

 

 

 

Receive(接收方)：

import java.io.IOException;

import java.net.DatagramPacket;

import java.net.DatagramSocket;

import java.net.SocketException;





public class ReceiverDemo1 {

	

	private static final int PORT = 8080;

	public static void main(String[] args) {

		receiveHandler();

	}



	private static void receiveHandler() {

		DatagramSocket receiveSocket = null;

		try {

			//在8080端口监听

			receiveSocket = new DatagramSocket(PORT);

			//while循环，一直在等待接收数据

			while(true){

				//创建一个包，并接收数据

				byte[] buf = new byte[1024];

				DatagramPacket dp = new DatagramPacket(buf, buf.length);

				receiveSocket.receive(dp);

				

				//取得IP地址和包里的数据内容

				String ip = dp.getAddress().getHostAddress();

				String data = new String(dp.getData(), 0, dp.getLength());

				

				System.out.println(ip + ":" + data);

			}

		} catch (SocketException e) {

			e.printStackTrace();

		} catch (IOException e) {

			e.printStackTrace();

		}finally{

			if(receiveSocket != null){

				receiveSocket.close();

			}

		}

	}

}

先启动接收方，再启动发送方