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Java for-loop generating MAC addresses

Trying to make a loop of MAC address values with:

String macAddr = "AA:BB:CC:DD:";
char[] chars = {'A', 'B', 'C', 'D', 'E', 'F'};
String[] strings = {"0", "0", "0", "0"};

for (int i=0; i<strings.length; i++)
{
    //counter from 0 to F
    for (int d = 0; d <= 9; d++)
    {
        strings[i] = ""+d;
        print();
    }
    for (int d = 0; d< chars.length; d++)
    {
        strings[i] = ""+chars[d];
        print();
    }
}

where print() is:

System.out.println(macAddr+strings[3]+strings[2]+":"+strings[1]+strings[0]);

But i'm getting run-over:

AA:BB:CC:DD:00:0D

AA:BB:CC:DD:00:0E

AA:BB:CC:DD:00:0F

AA:BB:CC:DD:00:0F

AA:BB:CC:DD:00:1F

AA:BB:CC:DD:00:2F

AA:BB:CC:DD:00:3F

The two problems are the dual values at each crossover (e.g. AA:BB:CC:DD:00:0F) and the values stopping at F on each value.

I'm trying to get them as:

AA:BB:CC:DD:00:0D

AA:BB:CC:DD:00:0E

AA:BB:CC:DD:00:0F

AA:BB:CC:DD:00:11

AA:BB:CC:DD:00:12

AA:BB:CC:DD:00:13

开发者_开发知识库

etc.

Cheers :)


Use a long to store your mac address and create a small function to convert it to a String.

public static String toMacString(long mac) {

    if (mac > 0xFFFFFFFFFFFFL || mac < 0)
        throw new IllegalArgumentException("mac out of range");

    StringBuffer m = new StringBuffer(Long.toString(mac, 16));
    while (m.length() < 12) m.insert(0, "0");

    for (int j = m.length() - 2; j >= 2; j-=2)
        m.insert(j, ":");
    return m.toString().toUpperCase();
}

public static void main(String[] args) {

    long mac = 0xAABBCCDD0000L;

    for (long i = 0; i < 1000; i++)
        System.out.println(toMacString(mac++));
}

Example output:

AA:BB:CC:DD:00:00
AA:BB:CC:DD:00:01
AA:BB:CC:DD:00:02
AA:BB:CC:DD:00:03
AA:BB:CC:DD:00:04
AA:BB:CC:DD:00:05
AA:BB:CC:DD:00:06
....
AA:BB:CC:DD:03:DF
AA:BB:CC:DD:03:E0
AA:BB:CC:DD:03:E1
AA:BB:CC:DD:03:E2
AA:BB:CC:DD:03:E3
AA:BB:CC:DD:03:E4
AA:BB:CC:DD:03:E5
AA:BB:CC:DD:03:E6
AA:BB:CC:DD:03:E7


Try this for keeping it simple:

public static void main(String... args) {
    String macAddr = "AA:BB:CC:DD:";
    for (int i = 0; i < 256; i++) {
        for (int j = 0; j < 256; j++) {
            String fullAddr = String.format(macAddr + "%02X:%02X", i, j);
            System.out.println(fullAddr);
        }
    }
}

Output (abbreviated):

AA:BB:CC:DD:00:00
AA:BB:CC:DD:00:01
AA:BB:CC:DD:00:..
AA:BB:CC:DD:00:10
AA:BB:CC:DD:00:0A
AA:BB:CC:DD:00:..
AA:BB:CC:DD:00:0F
AA:BB:CC:DD:00:10
AA:BB:CC:DD:00:..
AA:BB:CC:DD:00:FF
AA:BB:CC:DD:01:00
AA:BB:CC:DD:..:..
AA:BB:CC:DD:FF:FF


    String[] Mac = {"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"};
    Random rd = new Random();
    rd.nextInt(15);
    String result="";

    for(int i=0;i<6;i++){
        String a = Mac[rd.nextInt(15)];
        String b = Mac[rd.nextInt(15)];
        result+=a+b;
        if(i<5){
            result+=":";
        }

    }
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