网络编程
6 UDP
6.1 初识Tomcat
服务端
- 自定义 S
- Tomcat S
客户端
- 自定义 C
- 浏览器 B
6.2 UDP
6.2.1 udp实现发送消息
接收端：
package com.duo.lesson03;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;
public class UdpServerDemo1 {
public static void main(String[] args) throws Exception {
//开放端口
DatagramSocket datagramSocket = new DatagramSocket(9090);
//接收数据包
byte[] buffer = new byte[1024];
DatagramPacket datagramPacket = new DatagramPacket(buffer, 0, buffer.length);
datagramSocket.receive(datagramPacket); //阻塞接收
System.out.println(datagramPacket.getAddress().getHostAddress());
System.out.println(new String(datagramPacket.getData(), 0, datagramPacket.getLength()));
//关闭连接
datagramSocket.close();
}
}
发送端：
package com.duo.lesson03;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
//UDP不需要连接服务器
public class UdpClientDemo1 {
public static void main(String[] args) throws Exception {
//1.建立一个Socket用于发送包
DatagramSocket datagramSocket = new DatagramSocket();
//2.建一个包
String msg = "您收到一条新消息";
InetAddress inetAddress = InetAddress.getByName("localhost");
int port = 9090;
DatagramPacket datagramPacket = new DatagramPacket(msg.getBytes(), 0, msg.getBytes().length, inetAddress, port);
//3.发送包
datagramSocket.send(datagramPacket);
//4.关闭流
datagramSocket.close();
}
}
运行结果：
