Thrown by InstructionList.remove() when one or multiple disposed instruction are still being referenced by a InstructionTargeter object. I.e. the InstructionTargeter has to be notified that (one of) the InstructionHandle it is referencing is being removed from the InstructionList and thus not valid anymore. Making this an exception instead of a return value forces the user to handle these case explicitely in a try { ... } catch. The following code illustrates how this may be done:

     ...
     try {
	il.delete(start_ih, end_ih);
     } catch(TargetLostException e) {
       InstructionHandle[] targets = e.getTargets();
	 for(int i=0; i < targets.length; i++) {
	   InstructionTargeter[] targeters = targets[i].getTargeters();

	   for(int j=0; j < targeters.length; j++)
	     targeters[j].updateTarget(targets[i], new_target);
       }
     }