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.pack200; 018 019import org.objectweb.asm.ClassReader; 020 021/** 022 * Wrapper for ClassReader that enables pack200 to obtain extra class file information 023 */ 024public class Pack200ClassReader extends ClassReader { 025 026 private boolean lastConstantHadWideIndex; 027 private int lastUnsignedShort; 028 private boolean anySyntheticAttributes; 029 private String fileName; 030 031 /** 032 * @param b the contents of class file in the format of bytes 033 */ 034 public Pack200ClassReader(final byte[] b) { 035 super(b); 036 } 037 038 @Override 039 public int readUnsignedShort(final int index) { 040 // Doing this to check whether last load-constant instruction was ldc (18) or ldc_w (19) 041 // TODO: Assess whether this impacts on performance 042 final int unsignedShort = super.readUnsignedShort(index); 043 if (b[index - 1] == 19) { 044 lastUnsignedShort = unsignedShort; 045 } else { 046 lastUnsignedShort = Short.MIN_VALUE; 047 } 048 return unsignedShort; 049 } 050 051 @Override 052 public Object readConst(final int item, final char[] buf) { 053 lastConstantHadWideIndex = item == lastUnsignedShort; 054 return super.readConst(item, buf); 055 } 056 057 @Override 058 public String readUTF8(final int arg0, final char[] arg1) { 059 final String utf8 = super.readUTF8(arg0, arg1); 060 if (!anySyntheticAttributes && "Synthetic".equals(utf8)) { 061 anySyntheticAttributes = true; 062 } 063 return utf8; 064 } 065 066 public boolean lastConstantHadWideIndex() { 067 return lastConstantHadWideIndex; 068 } 069 070 public boolean hasSyntheticAttributes() { 071 return anySyntheticAttributes; 072 } 073 074 public void setFileName(final String name) { 075 this.fileName = name; 076 } 077 078 public String getFileName() { 079 return fileName; 080 } 081 082}