protected void copyAnnotationState(PDFAnnotation source, PDFAnnotation target) {
    super.copyAnnotationState(source, target);

    AnnotationStamp sourceStamp = (AnnotationStamp) source;
    AnnotationStamp targetStamp = (AnnotationStamp) target;
    targetStamp.setType(sourceStamp.getType(), sourceStamp.getOpacity());
  }
 public void initialize(PDFViewer viewer) {
   super.initialize(viewer);
   String val = getFeatureProperty(viewer, "stampList");
   if (val != null) {
     setStampList(val.split(", *"));
   }
   val = getFeatureProperty(viewer, "stampHeight");
   if (val != null) {
     try {
       setStampHeight(Math.max(10, Integer.parseInt(val)));
     } catch (Exception e) {
     }
   }
 }