前言

1.埠表示計算機的一個程式的程序：
2.不同的程序有不同的埠號，用來區分軟體
3.理論上規定了0~65536
4.TCP，UDP：65536*2 Tcp：80 udp:80,單個協議下，埠不能衝突
5.埠分類：
    共有埠0~1023
        HTTP:80    超文字傳輸協議
        HTTPS：443 超文字傳輸安全協議，基於ssl的http協議
        FTP：21  ，檔案傳輸協議
        Telent：23  遠端傳輸協議
    程式註冊埠：1024~49151
        Tomcat：8080
        MySQL：3306
        Oracle：1521
     動態，私有：49152~65535
 

簡單實現網路通訊

package com.cl.lesson01;


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

//封裝IP，InetAddress
public class TestInterAddress {
    public static void main(String[] args) {
        try {
            InetAddress interAddress1=InetAddress.getByName("127.0.0.1");
            System.out.println(interAddress1);
            InetAddress interAddress3
 
=InetAddress.getByName("localhost");
            System.out.println(interAddress3);
            InetAddress interAddress4=InetAddress.getLocalHost();
            System.out.println(interAddress4);

            //查詢網站IP地址
            InetAddress interAddress2=InetAddress.getByName("www.baidu.com");
            System.out.println(interAddress2);

            
 
//常用方法
            System.out.println(interAddress2.getAddress());
            System.out.println(interAddress2.getCanonicalHostName());//規範的名字
            System.out.println(interAddress2.getHostAddress());//ip
            System.out.println(interAddress2.getHostName());//域名

        }catch (UnknownHostException e){
            e.printStackTrace();
        }

    }
}



package com.cl.lesson01;

import java.net.InetSocketAddress;

//封裝計算機的ip+埠號，InetSocketAddress
public class TestInetSocketAddress {
    public static void main(String[] args) {

        InetSocketAddress socketAddress = new InetSocketAddress("127.0.0.1",8080);
        InetSocketAddress socketAddress2 = new InetSocketAddress("localhost",8080);
        System.out.println(socketAddress2);

        System.out.println(socketAddress.getAddress());
        System.out.println(socketAddress.getHostName());//地址
        System.out.println(socketAddress.getPort());//埠


    }
}