[Solved]lwjgl fullscreen cpu load problem

[nA1]

Hello all!
I spent some time learning basic java stuff since my last visit (as you people mentioned) and ended up with lwjgl.
I have a little problem which stops me from starting to learn opengl and from actual game making.

Here is the code first:

import org.lwjgl.LWJGLException;
import org.lwjgl.Sys;
import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.Display;


public class Game {
	long lastFrame;
	int fps;
	long lastFPS;
	boolean fullscreen = true;
	boolean vsync = true;
	int refrashRate = Display.getDesktopDisplayMode().getFrequency();
	int currentWidth = Display.getDesktopDisplayMode().getWidth();
	int currentHeight = Display.getDesktopDisplayMode().getHeight();
	boolean exitFromApp = true;

	public void start() {
		try {
			Display.setVSyncEnabled(vsync);
			Display.setFullscreen(fullscreen);
			Display.create();
		} catch (LWJGLException e) {
			e.printStackTrace();
			System.exit(0);
		}

		getDelta();
		lastFPS = getTime();

		while (!Display.isCloseRequested() && exitFromApp) {
			int delta = getDelta();

			update(delta);

			Display.update();
			Display.sync(refrashRate);
		}

		Display.destroy();
	}

	public void update(int delta) {
		while (Keyboard.next()) {
			if (Keyboard.getEventKeyState()) {
				if (Keyboard.getEventKey() == Keyboard.KEY_ESCAPE) {
					exitFromApp = false;
				}
				if (Keyboard.getEventKey() == Keyboard.KEY_F) {
					fullscreen = false;
					try {
						Display.setFullscreen(false);
					} catch (LWJGLException e) {
						e.printStackTrace();
						System.exit(0);
					}
				}
			}
		}

		updateFPS();
	}

	public int getDelta() {
		long time = getTime();
		int delta = (int) (time - lastFrame);
		lastFrame = time;

		return delta;
	}

	public long getTime() {
		return (Sys.getTime() * 1000) / Sys.getTimerResolution();
	}

	public void updateFPS() {
		if (getTime() - lastFPS > 1000) {
			Display.setTitle("FPS: " + fps);
			fps = 0;
			lastFPS += 1000;
		}
		fps++;
	}

	public static void main(String[] argv) {
		Game game = new Game();
		game.start();
	}
}

It’s just fullscreen window. If I add some graphics, calculations, else… then everything runs super fine and smooth. The problem is the cpu load. At the moment the program is launched one of the cpu cores gets 100% load all the time and my radiator cooler starts to spin faster. What is the problem here and what should I implement to solve this issue?