public void keyPressed(KeyEvent e) {
		int key=e.getKeyCode();
        if(key==KeyEvent.VK_UP)
            dy=-SPEED;
        if(key==KeyEvent.VK_DOWN)
            dy=SPEED;
        if(key==KeyEvent.VK_RIGHT)
            dx=SPEED;
        if(key==KeyEvent.VK_LEFT)
            dx=-SPEED;
        if(key==KeyEvent.VK_SPACE && !isCharging) {
        	chargeStart = System.currentTimeMillis();
        	isCharging = true;
        }
	}