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.commons.compress.harmony.unpack200.bytecode; 018 019import java.io.DataOutputStream; 020import java.io.IOException; 021import java.util.List; 022 023/** 024 * An entry in an exception table. 025 */ 026public class ExceptionTableEntry { 027 028 private final int startPC; 029 private final int endPC; 030 private final int handlerPC; 031 private final CPClass catchType; 032 033 private int startPcRenumbered; 034 private int endPcRenumbered; 035 private int handlerPcRenumbered; 036 private int catchTypeIndex; 037 038 /** 039 * Create a new ExceptionTableEntry. Exception tables are of two kinds: either a normal one (with a Throwable as the 040 * catch_type) or a finally clause (which has no catch_type). In the class file, the finally clause is represented 041 * as catch_type == 0. 042 * 043 * To create a finally clause with this method, pass in null for the catchType. 044 * 045 * @param startPC int 046 * @param endPC int 047 * @param handlerPC int 048 * @param catchType CPClass (if it's a normal catch) or null (if it's a finally clause). 049 */ 050 public ExceptionTableEntry(final int startPC, final int endPC, final int handlerPC, final CPClass catchType) { 051 this.startPC = startPC; 052 this.endPC = endPC; 053 this.handlerPC = handlerPC; 054 this.catchType = catchType; 055 } 056 057 public void write(final DataOutputStream dos) throws IOException { 058 dos.writeShort(startPcRenumbered); 059 dos.writeShort(endPcRenumbered); 060 dos.writeShort(handlerPcRenumbered); 061 dos.writeShort(catchTypeIndex); 062 } 063 064 public void renumber(final List byteCodeOffsets) { 065 startPcRenumbered = ((Integer) byteCodeOffsets.get(startPC)).intValue(); 066 final int endPcIndex = startPC + endPC; 067 endPcRenumbered = ((Integer) byteCodeOffsets.get(endPcIndex)).intValue(); 068 final int handlerPcIndex = endPcIndex + handlerPC; 069 handlerPcRenumbered = ((Integer) byteCodeOffsets.get(handlerPcIndex)).intValue(); 070 } 071 072 public CPClass getCatchType() { 073 return catchType; 074 } 075 076 public void resolve(final ClassConstantPool pool) { 077 if (catchType == null) { 078 // If the catch type is a finally clause 079 // the index is always 0. 080 catchTypeIndex = 0; 081 return; 082 } 083 catchType.resolve(pool); 084 catchTypeIndex = pool.indexOf(catchType); 085 } 086}