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.optimize; 22b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 23b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.*; 24b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.util.MethodLinker; 25b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.visitor.*; 26b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wangimport proguard.optimize.info.NoSideEffectMethodMarker; 27b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 28b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 29b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato/** 30b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This <code>ClassVisitor</code> and <code>MemberVisitor</code> 31b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * marks classes and class members it visits. The marked elements 32b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * will remain unchanged as necessary in the optimization step. 33b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 34b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang * @see NoSideEffectMethodMarker 35b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * @author Eric Lafortune 36b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato */ 37b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratopublic class KeepMarker 38b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimplements ClassVisitor, 39b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato MemberVisitor 40b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato{ 41b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // A visitor info flag to indicate the visitor accepter is being kept. 42b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato private static final Object KEPT = new Object(); 43b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 44b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 45b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for ClassVisitor. 46b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 47b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitProgramClass(ProgramClass programClass) 48b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 49b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato markAsKept(programClass); 50b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 51b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 52b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 53b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitLibraryClass(LibraryClass libraryClass) 54b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 55b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato markAsKept(libraryClass); 56b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 57b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 58b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 59b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for MemberVisitor. 60b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 61b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitProgramField(ProgramClass programClass, ProgramField programField) 62b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 63b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato markAsKept(programField); 64b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 65b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 66b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 67b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod) 68b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 69b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato markAsKept(MethodLinker.lastMember(programMethod)); 70b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 71b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 72b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 73b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitLibraryField(LibraryClass libraryClass, LibraryField libraryField) 74b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 75b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato markAsKept(libraryField); 76b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 77b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 78b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 79b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitLibraryMethod(LibraryClass libraryClass, LibraryMethod libraryMethod) 80b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 81b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato markAsKept(MethodLinker.lastMember(libraryMethod)); 82b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 83b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 84b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 85b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Small utility methods. 86b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 87b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato private static void markAsKept(VisitorAccepter visitorAccepter) 88b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 89b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato visitorAccepter.setVisitorInfo(KEPT); 90b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 91b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 92b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 93b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public static boolean isKept(VisitorAccepter visitorAccepter) 94b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 95b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang // We're also checking for the constant in NoSideEffectMethodMarker, 96b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang // to keep things simple. 97b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang Object visitorInfo = 98b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang MethodLinker.lastVisitorAccepter(visitorAccepter).getVisitorInfo(); 99b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang 100b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang return visitorInfo == KEPT || 101b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang visitorInfo == NoSideEffectMethodMarker.KEPT_BUT_NO_SIDE_EFFECTS; 102b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 103b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato} 104