package com.ydtech.utils;

import java.net.*;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class MacUtils {
    /***因为一台机器不一定只有一个网卡呀，所以返回的是数组是很合理的***/
    public static List<String> getMacList() throws Exception {
        java.util.Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces();
        StringBuilder sb = new StringBuilder();
        ArrayList<String> tmpMacList = new ArrayList<>();
        while (en.hasMoreElements()) {
            NetworkInterface iface = en.nextElement();
            List<InterfaceAddress> addrs = iface.getInterfaceAddresses();
            for (InterfaceAddress addr : addrs) {
                InetAddress ip = addr.getAddress();
                NetworkInterface network = NetworkInterface.getByInetAddress(ip);
                if (network == null) {
                    continue;
                }
                byte[] mac = network.getHardwareAddress();
                if (mac == null) {
                    continue;
                }
                sb.delete(0, sb.length());
                for (int i = 0; i < mac.length; i++) {
                    sb.append(String.format("%02X%s", mac[i], (i < mac.length - 1) ? "-" : ""));
                }
                tmpMacList.add(sb.toString());
            }
        }
        if (tmpMacList.isEmpty()) {
            return tmpMacList;
        }
        /***去重，别忘了同一个网卡的ipv4,ipv6得到的mac都是一样的，肯定有重复，下面这段代码是。。流式处理***/
        List<String> unique = tmpMacList.stream().distinct().collect(Collectors.toList());
        return unique;
    }

    public static String getLocalMac() {
        StringBuffer sb = new StringBuffer("");
        try {
            //获取网卡，获取地址
            InetAddress ia = InetAddress.getLocalHost();
            //System.out.println(ia);
            byte[] mac = NetworkInterface.getByInetAddress(ia).getHardwareAddress();

            //System.out.println("mac数组长度："+mac.length);


            for (int i = 0; i < mac.length; i++) {
                if (i != 0) {
                    sb.append("-");
                }

                //字节转换为整数
                int temp = mac[i] & 0xff;
                String str = Integer.toHexString(temp);

//                System.out.println("每8位:" + str);
                if (str.length() == 1) {
                    sb.append("0" + str);
                } else {
                    sb.append(str);
                }
            }
        } catch (Exception e) {
            //do nothing
        }

        System.out.println("本机MAC地址:" + sb.toString().toUpperCase());

        return sb.toString().toUpperCase();
    }

    public static void main(String[] args) throws Exception {
        long a = System.currentTimeMillis();
        System.out.println("进行 multi net address 测试===》");
        List<String> macs = getMacList();
        long b = System.currentTimeMillis();
        System.out.println("本机的mac网卡的地址有：" + macs);
        System.out.println("总耗时----" + (b - a) + "-----ms");
        getLocalMac();
    }
}