1b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato/* 2b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * ProGuard -- shrinking, optimization, obfuscation, and preverification 3b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * of Java bytecode. 4b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 52270795fbe0b277bfd49f40950ecaa78583175ccBrian Carlstrom * Copyright (c) 2002-2014 Eric Lafortune (eric@graphics.cornell.edu) 6b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 7b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This program is free software; you can redistribute it and/or modify it 8b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * under the terms of the GNU General Public License as published by the Free 9b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * Software Foundation; either version 2 of the License, or (at your option) 10b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * any later version. 11b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 12b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This program is distributed in the hope that it will be useful, but WITHOUT 13b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * more details. 16b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 17b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * You should have received a copy of the GNU General Public License along 18b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * with this program; if not, write to the Free Software Foundation, Inc., 19b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato */ 21b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratopackage proguard.classfile.util; 22b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 23b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.*; 24b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.attribute.Attribute; 25b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.attribute.visitor.AttributeVisitor; 26b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.constant.*; 27b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.constant.visitor.ConstantVisitor; 28b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.visitor.ClassVisitor; 29b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 30b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato/** 31b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This ClassVisitor shares strings in the class files that it visits. 32b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 33b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * @author Eric Lafortune 34b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato */ 35b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratopublic class StringSharer 36b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoextends SimplifiedVisitor 37b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimplements ClassVisitor, 38b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato ConstantVisitor, 39b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato AttributeVisitor 40b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato{ 41b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // A fields acting as an argument for the visitor methods. 42b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato private String name; 43b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato private String type; 44b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 45b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 46b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for ClassVisitor. 47b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 48b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitProgramClass(ProgramClass programClass) 49b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 50b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Replace name strings in the constant pool by shared strings. 51b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato programClass.constantPoolEntriesAccept(this); 52b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 53b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Replace attribute name strings in the constant pool by internalized 54b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // strings. 55b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato programClass.attributesAccept(this); 56b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 57b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 58b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 59b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitLibraryClass(LibraryClass libraryClass) 60b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 61b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Replace the super class name string by the shared name string. 62b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato Clazz superClass = libraryClass.superClass; 63b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (superClass != null) 64b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 65b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato libraryClass.superClassName = superClass.getName(); 66b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 67b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang 68b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang // Replace the interface name strings by the shared name strings. 69b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang if (libraryClass.interfaceNames != null) 70b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang { 71b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang String[] interfaceNames = libraryClass.interfaceNames; 72b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang Clazz[] interfaceClasses = new Clazz[interfaceNames.length]; 73b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang 74b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang for (int index = 0; index < interfaceNames.length; index++) 75b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang { 76b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang // Keep a reference to the interface class. 77b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang Clazz interfaceClass = interfaceClasses[index]; 78b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang if (interfaceClass != null) 79b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang { 80b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang interfaceNames[index] = interfaceClass.getName(); 81b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang } 82b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang } 83b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang } 84b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 85b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 86b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 87b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for ConstantVisitor. 88b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 89b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 90b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitAnyConstant(Clazz clazz, Constant constant) {} 91b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 92b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 93b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang public void visitStringConstant(Clazz clazz, StringConstant stringConstant) 94b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 95b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato Member referencedMember = stringConstant.referencedMember; 96b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (referencedMember != null) 97b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 98b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato Clazz referencedClass = stringConstant.referencedClass; 99b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 100b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Put the actual class member's name in the class pool. 101b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato name = referencedMember.getName(referencedClass); 102b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato clazz.constantPoolEntryAccept(stringConstant.u2stringIndex, this); 103b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 104b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 105b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 106b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 107b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitAnyRefConstant(Clazz clazz, RefConstant refConstant) 108b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 109b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato Member referencedMember = refConstant.referencedMember; 110b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (referencedMember != null) 111b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 112b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato Clazz referencedClass = refConstant.referencedClass; 113b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 114b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Put the actual class member's name and type strings in the class 115b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // pool. 116b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato name = referencedMember.getName(referencedClass); 117b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato type = referencedMember.getDescriptor(referencedClass); 118b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato clazz.constantPoolEntryAccept(refConstant.u2nameAndTypeIndex, this); 119b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 120b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 121b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 122b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 123b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitNameAndTypeConstant(Clazz clazz, NameAndTypeConstant nameAndTypeConstant) 124b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 125b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (name != null) 126b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 127b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Put the actual class member's name and type strings in the class 128b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // pool. 129b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato clazz.constantPoolEntryAccept(nameAndTypeConstant.u2nameIndex, this); 130b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato name = type; 131b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato clazz.constantPoolEntryAccept(nameAndTypeConstant.u2descriptorIndex, this); 132b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 133b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 134b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 135b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 136b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitClassConstant(Clazz clazz, ClassConstant classConstant) 137b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 138b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato Clazz referencedClass = classConstant.referencedClass; 139b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (referencedClass != null) 140b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 141b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Put the actual class's name string in the class pool. 142b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato name = referencedClass.getName(); 143b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato clazz.constantPoolEntryAccept(classConstant.u2nameIndex, this); 144b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 145b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 146b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 147b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 148b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitUtf8Constant(Clazz clazz, Utf8Constant utf8Constant) 149b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 150b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Do we have a new string to put into this constant? 151b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (name != null) 152b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 153b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Replace the string, if it's actually the same. 154b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (name.equals(utf8Constant.getString())) 155b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 156b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato utf8Constant.setString(name); 157b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 158b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 159b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato name = null; 160b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 161b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 162b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 163b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 164b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for AttributeVisitor. 165b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 166b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitAnyAttribute(Clazz clazz, Attribute attribute) 167b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 168b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Put the internalized attribute's name string in the class pool. 169b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato name = attribute.getAttributeName(clazz).intern(); 170b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato clazz.constantPoolEntryAccept(attribute.u2attributeNameIndex, this); 171b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 172b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato} 173