How do I read the status of Num Lock key?

This example show you how to detect if the Num Lock key is in active mode.

package org.kodejava.example.awt;

import java.awt.Toolkit;
import java.awt.event.KeyEvent;

public class NumLockState {
    public static void main(String[] args) {
        Toolkit toolkit = Toolkit.getDefaultToolkit();

        //
        // Get the locking state of the Num Lock button. If it is "on"
        // this method return boolean true value.
        //
        boolean isOn = toolkit.getLockingKeyState(KeyEvent.VK_NUM_LOCK);

        System.out.println("NumLock button is " + (isOn ? "on" : "off"));
    }
}

If you run the program you will get an output telling you that the num lock button is active or not active.

Wayan Saryada

Programmer, runner, recreational diver, live in the island of Bali, Indonesia 🇮🇩. Mostly programming in Java, creating web based application with Spring Framework, Hibernate / JPA.

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