package com.atguigu.java1;

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

import org.junit.Test;
//UDP编程的实现
public class TestUDP {

// 发送端
@Test
public void send() {
DatagramSocket ds = null;
try {
ds = new DatagramSocket();
byte[] b = "你好，我是要发送的数据".getBytes();
//创建一个数据报：每一个数据报不能大于64k，都记录着数据信息，发送端的IP、端口号,以及要发送到
//的接收端的IP、端口号。
DatagramPacket pack = new DatagramPacket(b, 0, b.length,
InetAddress.getByName("127.0.0.1"), 9090);

ds.send(pack);
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(ds != null){
ds.close();

}
}

}

// 接收端
@Test
public void rceive() {
DatagramSocket ds = null;
try {
ds = new DatagramSocket(9090);
byte[] b = new byte[1024];
DatagramPacket pack = new DatagramPacket(b, 0, b.length);
ds.receive(pack);

String str = new String(pack.getData(), 0, pack.getLength());
System.out.println(str);
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(ds != null){
ds.close();

}
}




}
}

UDP