001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.bcel.generic; 018 019/** 020 * Thrown by InstructionList.remove() when one or multiple disposed instructions are still being referenced by an 021 * InstructionTargeter object. I.e. the InstructionTargeter has to be notified that (one of) the InstructionHandle it is 022 * referencing is being removed from the InstructionList and thus not valid anymore. 023 * 024 * <p> 025 * Making this an exception instead of a return value forces the user to handle these case explicitly in a try { ... } 026 * catch. The following code illustrates how this may be done: 027 * </p> 028 * 029 * <PRE> 030 * ... 031 * try { 032 * il.delete(start_ih, end_ih); 033 * } catch (TargetLostException e) { 034 * for (InstructionHandle target : e.getTargets()) { 035 * for (InstructionTargeter targeter : target.getTargeters()) { 036 * targeter.updateTarget(target, new_target); 037 * } 038 * } 039 * } 040 * </PRE> 041 * 042 * @see InstructionHandle 043 * @see InstructionList 044 * @see InstructionTargeter 045 */ 046public final class TargetLostException extends Exception { 047 048 private static final long serialVersionUID = -6857272667645328384L; 049 private final InstructionHandle[] targets; 050 051 TargetLostException(final InstructionHandle[] t, final String mesg) { 052 super(mesg); 053 targets = t; 054 } 055 056 /** 057 * @return list of instructions still being targeted. 058 */ 059 public InstructionHandle[] getTargets() { 060 return targets; 061 } 062}