This is the second half of bug 4650997, dealing with the performance issue.

Here's the test from the original submitter:

A slight modification to the example shows that 1.4 also suffers a huge
performance degradation over 1.3, even though a feature of 1.4 is supposed to be
improved graphics 2D performance. On the Windows2000 platform the attached
example runs in about 3.3 seconds under 1.3.1, but it takes about 20 seconds
under 1.4 (it does not matter whether or not the bounding box is drawn).

Here is the example that shows the performance problem:

<<TL.java>>
import java.awt.*;
import java.awt.event.*;
import java.text.*;
import java.awt.font.*;
import java.awt.image.*;
import java.awt.geom.*;
import java.util.*;

import javax.swing.*;

public class TL extends JComponent{
  int number = 360;
  boolean print = false;
  boolean box = true;
  int counter = 0;
  // Text we render
  String text = ".This is a STRINg.";

  // The following transform performs a flip along the x axis
  AffineTransform flip;

  // Rendering context parameters
  Font font = new Font("Default", Font.PLAIN, 24);
  Font flippedFont;

  public TL(){
    setPreferredSize(new Dimension(700,700));
  }

  public void paint(Graphics _g){
    long start = System.currentTimeMillis();
    Graphics2D g = (Graphics2D)_g;
    Dimension d = getSize();
    counter++;
    int x = d.width/2;
    int y = d.height/2;
    FontRenderContext frc = g.getFontRenderContext();

    for (int i = 0; i < number; i++) {
double angle = -Math.PI*2.0/number*i;
flip = AffineTransform.getRotateInstance(angle);
flippedFont = font.deriveFont(flip);
TextLayout tl = new TextLayout(text, flippedFont, frc);
Rectangle2D bb = tl.getBounds();
g.setPaint(Color.black);
tl.draw(g, x, y);
g.setPaint(Color.red);
if (box) {
g.drawRect(x + (int) bb.getX(), y + (int) bb.getY(),
(int) bb.getWidth(), (int) bb.getHeight());
}

if (print && counter == 1) {
System.out.println("Angle: "+angle);
System.out.println("getAscent: "+tl.getAscent());
System.out.println("getAdvance: "+tl.getAdvance());
System.out.println("getBaseline: "+tl.getBaseline());
System.out.println("getBounds: "+tl.getBounds());
System.out.println("getDescent: "+tl.getDescent());
System.out.println("getLeading: "+tl.getLeading());
System.out.println("getVisibleAdvance: "+tl.getVisibleAdvance());
System.out.println(".");
} else if (print && i == 0) {
System.out.println("Paint, counter="+counter);
}
    }
    System.out.println("Time="+(System.currentTimeMillis()-start));
  }

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

class SnippetFrame extends JFrame{
  /**
   * @param cmp component to add to the frame's content pane
   */
  public SnippetFrame(JComponent cmp){
    super();

    getContentPane().add(cmp);

    // Set white background as a default
    getContentPane().setBackground(Color.white);

    // Pack to fit cmp's preferred size
    pack();

    // Add a listener to close the application when
    // user closes the frame.
    addWindowListener(new WindowAdapter(){
      public void windowClosing(WindowEvent evt){
System.exit(0);
      }
    });

    setVisible(true);
  }
}