Name: dgC58589 Date: 01/08/98


/*
  As illustrated below, PixelGrabber applied to a BufferedImage fails with
  a NullPointerException:

  java.lang.NullPointerException:
        at java.awt.image.PixelGrabber.grabPixels(PixelGrabber.java:241)
        at java.awt.image.PixelGrabber.grabPixels(PixelGrabber.java:217)
        at bug_report4.init(bug_report4.java:35)
        at sun.applet.AppletPanel.run(AppletPanel.java:283)
        at java.lang.Thread.run(Thread.java:484)

  This bug manifests itself under at least JDK 1.2beta2 running on Win 95,
  but probably on all hardware platforms.

  The problem seems to be that BufferedImage.getSource() returns null (see
  BufferedImageSource.java line 813).
*/

import java.awt.*;
import java.awt.image.*;
import java.applet.Applet;

public class bug_report4 extends Applet {
  public void init()
    {
      BufferedImage result_image;
      int[] pixels = new int[64*64];
      PixelGrabber grabber;

      /* create a transparent in-memory image */
      result_image = GraphicsEnvironment.getLocalGraphicsEnvironment()
        .getDefaultScreenDevice().getDefaultConfiguration()
        .createCompatibleImage(64,64,Transparency.TRANSLUCENT);

      /* This is the problem (?) */
      System.out.println("result_image.getSource() = " +
        result_image.getSource());

      /* grab the pixels */
      grabber = new PixelGrabber(result_image, 0,0, 64,64, pixels, 0, 64);
      try {
        /**** This fails with a NullPointer exception ****/
        grabber.grabPixels();
      } catch (InterruptedException e) {
        System.out.println(e);
      }
      if ((grabber.getStatus() & ImageObserver.ABORT) != 0)
        System.out.println("Grabber failed");
    }
 }

// <applet codebase="." code="bug_report4" height=100 width=100></applet>
(Review ID: 22856)
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