Java自學-網路程式設計（1）

1、網課截圖

1.1 什麼是計算機網路

1.2 網路通訊的兩個要素

1.3 IP地址

package lesson01;

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

/**
 * Author: Gu Jiakai
 * Date: 2021/7/31 17:05
 * FileName: TestInetAddress
 * Description:
 */
//測試ip。
public class TestInetAddress {
    public static void main(String[] args) {
        try {
//            查詢本機地址。
            InetAddress  inetAddress1 = InetAddress.getByName("127.0.0.1");
            System.out.println(inetAddress1);
            InetAddress  inetAddress3 = InetAddress.getByName("localhost");
            System.out.println(inetAddress3);
            InetAddress  inetAddress4 = InetAddress.getLocalHost();
            System.out.println(inetAddress4);

//            查詢網站ip地址。
            InetAddress  inetAddress2 = InetAddress.getByName("www.baidu.com");
            System.out.println(inetAddress2);

//            常用方法。
//            System.out.println(inetAddress2.getAddress());
            System.out.println(inetAddress2.getCanonicalHostName());//規範的名字。
            System.out.println(inetAddress2.getHostAddress());//ip
            System.out.println(inetAddress2.getHostName());//域名，或者本機電腦的名字。
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }
}