JavaUDP,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