public void resume() {
   try {
     suspended = false;
     interpreter.resume();
   } catch (WrappedException ex) {
     handleWrappedException(ex);
   }
 }
 public void stepForward() {
   try {
     interpreter.resume();
     interpreter.runCycle();
     interpreter.suspend();
   } catch (WrappedException ex) {
     handleWrappedException(ex);
   }
 }