I copied code from one of posts that in theory should work but it didn't.

Code I copied:

public class Keyboard {
    private static final Map<Integer, Boolean> pressedKeys = new HashMap<>();
    
    static {
        KeyboardFocusManager.getCurrentKeyboardFocusManager().addKeyEventDispatcher(event -> {
            synchronized (Keyboard.class) {
                if (event.getID() == KeyEvent.KEY_PRESSED) pressedKeys.put(event.getKeyCode(), true);
                else if (event.getID() == KeyEvent.KEY_RELEASED) pressedKeys.put(event.getKeyCode(), false);
                return false;
            }
        });
    }
    
    public static boolean isKeyPressed(int keyCode) { // Any key code from the KeyEvent class
        return pressedKeys.getOrDefault(keyCode, false);
    }
}

it gives two errors:

Cannot define static initializer in inner type jWindowComponent.Keyboard

The method isKeyPressed cannot be declared static; static methods can only be declared in a static or top level type

I tried every thing to fix it i could come up with but with no success. I wanted to make specialized UI for little project i am working. I need some way that i can change parameters of graph renderer mid render and needed something like this:

if (Keyboard.isKeyPressed(KeyEvent.VK_A)) {
    x=0;
    y=0;
}

When I press key it will zoom in or it will pump up resolution or move certain direction. I have an idea on how to do it but i have no idea how to make it respond to key presses. It is my first time doing any kind of input other than using terminal and i really want to do it outside of terminal. I tried everything i found and i am either blind or i have no idea how to make it work. I tried everything from this post but nothing worked.

Anyway it may be some weird shenanigans in other parts of my code here:

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.*;
import java.awt.event.KeyEvent;
import java.util.HashMap;
import java.util.Map;



import javax.swing.JFrame;

public class jWindowComponent extends Canvas {

    private static final long serialVersionUID = 1L;
    private static final int WIDTH = 1000; // Additional pixels needed for the frame
    private static final int HEIGHT = 1000; // Additional pixels needed for the frame

    @Override
    public void paint(Graphics g) {
        super.paint(g);
        long percent = 0;
        long percheck = 0;
        for (int r = 0; r <= 2; r  ) {
            for (int y = 0; y < HEIGHT; y  ) {
                for (int x = 0; x < WIDTH; x  ) {
                    if (Keyboard.isKeyPressed(KeyEvent.VK_A)) {
                        x=0;
                        y=0;
                    }
                    if (x==y) {
                        g.setColor(Color.BLACK);
                    } else {
                        g.setColor(Color.WHITE);
                    }
                    g.fillRect(x, y, 1, 1);
                }
                //percent = (long) (y * 100 / HEIGHT);
                //if (percent == percheck) {
                //    // block of code to be executed if the condition is true
                //} else {
                //    System.out.print(String.format("\033[