基于UDP无连接实现通信

Question

初学网络，越简单约好。

Answer 1

import java.net.*;
public class UDPClient {
public static void main(String[] args) throws Exception{
DatagramSocket ds=new DatagramSocket();
String s="hi ! ";
byte[] bs=s.getBytes();
DatagramPacket letter1 = new DatagramPacket(bs,0,bs.length,InetAddress.getLocalHost(),10000);
ds.send(letter1);
byte[] bs2=new byte[100];
DatagramPacket receiveLetter=new DatagramPacket(bs2,0,bs2.length);
ds.receive(receiveLetter);
byte[] bs3=receiveLetter.getData();
int offset=receiveLetter.getOffset();
int length=receiveLetter.getLength();
String text=new String(bs3,offset,length);
System.out.println(text);
System.out.println(InetAddress.getLocalHost());
ds.close();
}

}

import java.net.*;
public class UDPServer {
public static void main(String[] args) throws Exception{
DatagramSocket ds=new DatagramSocket(10000);
while(true){
byte[] bs=new byte[100];
DatagramPacket receive=new DatagramPacket(bs,0,bs.length);
ds.receive(receive);

        InetAddress address=receive.getAddress();
        int port = receive.getPort();
        String text="您好，这是服务器端发送的广播!";
        byte[] bs2=text.getBytes();
        DatagramPacket sendLetter=new DatagramPacket(bs2,0,bs2.length,address,port);
        ds.send(sendLetter);

        byte[] bs3=receive.getData();
        int offset=receive.getOffset();
        int length=receive.getLength();
        String text1=new String(bs3,offset,length);
        System.out.println(text1);
        System.out.println("地址:"+InetAddress.getLocalHost()+"端口:"+port);

    }

}