Name: rlT66838 Date: 09/01/99


Deriving a transformed font causes a large memory leak.
An application that must derive many fonts crashes with an
Out of Memory exception.
Sample code follows:

import java.awt.geom.*;
import java.awt.*;

public class Leak {

  static Runtime runtime = Runtime.getRuntime();
  static Font base = new Font("Arial", Font.PLAIN, 12);
  static AffineTransform at = new AffineTransform(0.2, 0.0, 0.0, 0.2, 5.0, 5.0);
  static long start = 0;
  static long end = 0;

  public static void mem(String msg) {
    runtime.gc();
    end = runtime.totalMemory() - runtime.freeMemory();
    if (start == 0) {
      System.out.println(msg + ": Memory used = " + end);
    } else {
      System.out.println(msg + ": Memory used = " + end +
                               " change = " + (end - start));
    }
    start = end;
  }

  public static void main(String[] args) {
    base.deriveFont(at);
    mem("Start ");
    for (int i = 0; i < 10000; i++) {
      base.deriveFont(at);
    }
    mem("Derive font ");
  }
}
(Review ID: 94581)
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I found this bug in Solaris as well:

figjam:src/java/bhpit 274$ uname -a
SunOS figjam 5.7 Generic sun4u sparc SUNW,Ultra-5_10
figjam:src/java/bhpit 276$ java -version
java version "1.2.2"
Classic VM (build JDK-1.2.2-W, native threads, sunwjit)