Decorating Eclipse icons with status indicators

gistfile1.java

private  static  final  Point size  = new  Point(16, 16);
private  Image getDecoratedImage(ImageRegistry registry, 
  String baseImageId, 
  IStatus status){ 

  ImageDescriptor overlay = null;
  Image baseImage = registry.get(baseImageId);
  switch (status.getSeverity()) {
  case IStatus.ERROR:
   overlay = PlatformUI.getWorkbench().getSharedImages()
     .getImageDescriptor(ISharedImages.IMG_DEC_FIELD_ERROR);
   break;
  case IStatus.WARNING:
   overlay = PlatformUI.getWorkbench().getSharedImages()
     .getImageDescriptor(ISharedImages.IMG_DEC_FIELD_WARNING);
   break;
  default:
   return baseImage;
  }
  // Construct a new image identifier
  String decoratedImageId = baseImageId.concat(String.valueOf(status
    .getSeverity()));
  // Return the stored image if we have one
  if (registry.get(decoratedImageId) == null) {
   // Otherwise create a new image and store it
   DecorationOverlayIcon decoratedImage = new DecorationOverlayIcon(
     baseImage, new ImageDescriptor[] { null, null, null,
       overlay, null }, size) {
   };
   registry.put(decoratedImageId, decoratedImage);
  }
  return registry.get(decoratedImageId);
}