1.1 计算机网络

1.2 网络通信的要素

1.3 ip

常用方法部分了解

package com.kuang.lesson01;

import java.net.InetAddress;
import java.net.UnknownHostException;

//测试IP
public class TestInetAddress {
    public static void main(String[] args) {
        try {
            //InetAddress里面没有构造器和字段，所以不能new 只能通过静态方法返回过来
            InetAddress inetAddress1 = InetAddress.getByName("127.0.0.1");
            System.out.println(inetAddress1);
            InetAddress inetAddress2 = InetAddress.getByName("localhost");//不同方式获得本机ip
            System.out.println(inetAddress2);
            InetAddress inetAddress3 = InetAddress.getLocalHost();
            System.out.println(inetAddress3);

            //查询网站ip地址
            InetAddress inetAddress4 = InetAddress.getByName("www.baidu.com");
            System.out.println(inetAddress4);

        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }
}
/127.0.0.1
localhost/127.0.0.1
DESKTOP-2GITFTM/192.168.3.30
www.baidu.com/110.242.68.3

1.4 端口Port

1.5 通信协议

计算机之间如何交流

网络通信协议：针对网络产生一种协议

1.6 TCP实现聊天

1.6.1 TCP文件上传

1.7 UDP

1.7.1 UDP消息发送

被挡住那里是接收数据包

1.7.2 UDP聊天室