Really slow obtaining font metrics

So the problem I have is that I start my application by displaying a simple menu. To size and align the text correctly I need to obtain font metrics and I cannot find a way to do it quickly. I tested my program and it looks like whatever method I use to obtain font metrics the first call takes over 500 milliseconds!? Because of it the time it takes to start-up my application is much longer than necessary.

I don't know if it is platform specific or not, but just in case, I'm using Mac OS 10.6.2 on MacBook Pro (hardware isn't an issue here).

If you know a way of obtaining font metrics quicker please help.

I tried these 3 methods for obtaining the font metrics and the first call is always very slow, no matter which method I choose.

import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.font.FontRenderContext;
import java.awt.font.LineMetrics;

import javax.swing.JFrame;

public class FontMetricsTest extends JFrame {
 public FontMetricsTest() {
  setVisible(true);
  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 }

 @Override
 public void paint(Graphics g) {
  Graphics2D g2 = (Graphics2D) g;

  Font font = new Font("Dialog", Font.BOLD, 10);
  long start = System.currentTimeMillis();

  FontMetrics fontMetrics = g2.getFontMetrics(font);
//  LineMetrics fontMetrics1 =
//     font.getLineMetrics("X", new FontRenderContext(null, false开发者_高级运维, false));
//  FontMetrics fontMetrics2 = g.getFontMetrics();

  long end = System.currentTimeMillis();
  System.out.println(end - start);
  g2.setFont(font);
 }

 public static void main(String[] args) {
  new FontMetricsTest();
 }
}

---

While I can't tell you how to get around the issue itself, you can use this method to decide exactly when to init it:

new BufferedImage(1, 1, BufferedImage.TYPE_BYTE_GRAY).createGraphics().getFontMetrics();

This is useful because you can put it anywhere - so, for example, you could do it while you display a loading screen or something. If you use a Graphics object during paint(), then you're restricted to only initializing while rendering.

EDIT:

In fact, this can be reduced to:

FontUtilities.getFont2D(new Font("Dialog", 0, 12));

(The slow part is the getFont2D call, not the Font constructor.)

EDIT 2:

And, finally, this can be reduced to:

sun.font.FontManagerFactory.getInstance();

The issue is that this singleton class needs a long time to start up, as it enumerates all of the system fonts.

EDIT 3:

There is no good way around this issue if you want to use the standard Graphics system.

---

No real clue as for why it's so slow, but for method 3, shouldn't you be calling 'setFont' first?

public void paint(Graphics g) {
    g.setFont(font);
    FontMetrics fm = g.getFontMetrics();
}

It doesn't make a difference speed-wise, though :-(

Also, it's a bit uneconomic to create a new Font each time paint() is called (which happens a lot), you could move that to your constructor. But that cannot be the problem here, as you start measuring the time only after the Font has been created.