http://www.aspectj.org: The AspectJ weaver introduces advices to java classes
  • Andy Clement 
package org.aspectj.apache.bcel.generic;

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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);
      }
    }



Author: M. Dahm
See Also:
Version:$Id: TargetLostException.java,v 1.3 2008/05/28 23:52:55 aclement Exp $
/**
 * 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:
 *
 * <PRE>
 *     ...
 *     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);
 *       }
 *     }
 * </PRE>
 *
 * @see InstructionHandle
 * @see InstructionList
 * @see InstructionTargeter
 * @version $Id: TargetLostException.java,v 1.3 2008/05/28 23:52:55 aclement Exp $
 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
 */
// OPTIMIZE make unchecked, or get rid of it!
public final class TargetLostException extends Exception {
  private InstructionHandle[] targets;

  TargetLostException(InstructionHandle[] t, String mesg) {
    super(mesg);
    targets = t;
  }

  
Returns:list of instructions still being targeted.
/**
   * @return list of instructions still being targeted.
   */
  public InstructionHandle[] getTargets() { return targets; }
}