public static VisualiserUpdateJob getInstance() {
   if (theJob == null) {
     theJob = new VisualiserUpdateJob(VisualiserMessages.Jobs_VisualiserUpdate);
     theJob.setUser(true);
     theJob.setPriority(Job.INTERACTIVE);
   }
   return theJob;
 }
 /** Refresh the Visualiser views. */
 public static void refresh() {
   if (visualiser != null && visualiser.getSite() != null) {
     if (visualiser.getSite().getPage().isPartVisible(visualiser)) {
       VisualiserUpdateJob.getInstance().schedule();
     } else {
       visualiser.setNeedsUpdating();
     }
   }
 }