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@jumar
Last active March 1, 2025 13:43
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Send magic wol packet java
import java.io.*;
import java.net.*;
public class WakeOnLan {
public static final int PORT = 9;
public static void main(String[] args) {
if (args.length != 2) {
System.out.println("Usage: java WakeOnLan <broadcast-ip> <mac-address>");
System.out.println("Example: java WakeOnLan 192.168.0.255 00:0D:61:08:22:4A");
System.out.println("Example: java WakeOnLan 192.168.0.255 00-0D-61-08-22-4A");
System.exit(1);
}
String ipStr = args[0];
String macStr = args[1];
try {
byte[] macBytes = getMacBytes(macStr);
byte[] bytes = new byte[6 + 16 * macBytes.length];
for (int i = 0; i < 6; i++) {
bytes[i] = (byte) 0xff;
}
for (int i = 6; i < bytes.length; i += macBytes.length) {
System.arraycopy(macBytes, 0, bytes, i, macBytes.length);
}
InetAddress address = InetAddress.getByName(ipStr);
DatagramPacket packet = new DatagramPacket(bytes, bytes.length, address, PORT);
DatagramSocket socket = new DatagramSocket();
socket.send(packet);
socket.close();
System.out.println("Wake-on-LAN packet sent.");
}
catch (Exception e) {
System.out.println("Failed to send Wake-on-LAN packet: + e");
System.exit(1);
}
}
private static byte[] getMacBytes(String macStr) throws IllegalArgumentException {
byte[] bytes = new byte[6];
String[] hex = macStr.split("(\\:|\\-)");
if (hex.length != 6) {
throw new IllegalArgumentException("Invalid MAC address.");
}
try {
for (int i = 0; i < 6; i++) {
bytes[i] = (byte) Integer.parseInt(hex[i], 16);
}
}
catch (NumberFormatException e) {
throw new IllegalArgumentException("Invalid hex digit in MAC address.");
}
return bytes;
}
}
@Shterneregen
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Hay! Thanks for sharing, your gist saved my time! I re-wrote it in Kotlin service to use in Spring Boot app. Hope it also saves somebody else time!
https://gist.github.com/Shterneregen/14243dcecdad03c068176d9c24eafb59

@kevinturbo867
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God bless you!

@thesaguaro
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Thank you so much for this!

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