Simple WoL (Wake on Lan) in Java

wol.java

package me.nithanim.test.wol;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;

public class Main {
    public static void main(String[] args) throws IOException {
        // 0B-5A-70-78-C0-D6
        long mac = 0x0B5A7078C0D6L;
        new Main().sendWol(mac);
    }

    public void sendWol(long mac) throws IOException {
        byte[] data = buildPacket(mac);
        sendPacket(data);
    }

    private byte[] buildPacket(long mac) {
        byte[] data = new byte[(1 + 16) * 6];
        writeArrayPart(data, 0, 0xFFFFFFFFFFFFL);
        for (int i = 1; i <= 16; i++) {
            writeArrayPart(data, i, mac);
        }
        return data;
    }

    private void writeArrayPart(byte[] data, int idx, long value) {
        int offset = idx * 6;
        data[offset + 0] = (byte) (value >>> (8 * 5));
        data[offset + 1] = (byte) (value >>> (8 * 4));
        data[offset + 2] = (byte) (value >>> (8 * 3));
        data[offset + 3] = (byte) (value >>> (8 * 2));
        data[offset + 4] = (byte) (value >>> (8 * 1));
        data[offset + 5] = (byte) (value >>> (8 * 0));
    }

    private void sendPacket(byte[] data) throws IOException {
        try (DatagramSocket socket = new DatagramSocket()) {
            // binding the socket to ports < 1024 not possible, but sending works
            DatagramPacket packet = new DatagramPacket(data, data.length, new InetSocketAddress("255.255.255.255", 9));
            socket.send(packet);
        }
    }
}