1/* 2 * ProGuard -- shrinking, optimization, obfuscation, and preverification 3 * of Java bytecode. 4 * 5 * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu) 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the Free 9 * Software Foundation; either version 2 of the License, or (at your option) 10 * any later version. 11 * 12 * This program is distributed in the hope that it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15 * more details. 16 * 17 * You should have received a copy of the GNU General Public License along 18 * with this program; if not, write to the Free Software Foundation, Inc., 19 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21package proguard.shrink; 22 23import proguard.classfile.*; 24import proguard.classfile.visitor.MemberVisitor; 25 26/** 27 * This MemberVisitor delegates all its method calls to another MemberVisitor, 28 * but only for Member objects that are marked as used. 29 * 30 * @see UsageMarker 31 * 32 * @author Eric Lafortune 33 */ 34public class UsedMemberFilter 35implements MemberVisitor 36{ 37 private final UsageMarker usageMarker; 38 private final MemberVisitor memberVisitor; 39 40 41 /** 42 * Creates a new UsedClassFilter. 43 * @param usageMarker the usage marker that is used to mark the classes 44 * and class members. 45 * @param memberVisitor the member visitor to which the visiting will be 46 * delegated. 47 */ 48 public UsedMemberFilter(UsageMarker usageMarker, 49 MemberVisitor memberVisitor) 50 { 51 this.usageMarker = usageMarker; 52 this.memberVisitor = memberVisitor; 53 } 54 55 56 // Implementations for MemberVisitor. 57 58 59 public void visitProgramField(ProgramClass programClass, ProgramField programField) 60 { 61 if (usageMarker.isUsed(programField)) 62 { 63 memberVisitor.visitProgramField(programClass, programField); 64 } 65 } 66 67 68 public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod) 69 { 70 if (usageMarker.isUsed(programMethod)) 71 { 72 memberVisitor.visitProgramMethod(programClass, programMethod); 73 } 74 } 75 76 77 public void visitLibraryField(LibraryClass libraryClass, LibraryField libraryField) 78 { 79 if (usageMarker.isUsed(libraryField)) 80 { 81 memberVisitor.visitLibraryField(libraryClass, libraryField); 82 } 83 } 84 85 86 public void visitLibraryMethod(LibraryClass libraryClass, LibraryMethod libraryMethod) 87 { 88 if (usageMarker.isUsed(libraryMethod)) 89 { 90 memberVisitor.visitLibraryMethod(libraryClass, libraryMethod); 91 } 92 } 93} 94