/* $Id: AttributeShrinker.java,v 1.17.2.1 2006/01/16 22:57:56 eric Exp $ * * ProGuard -- shrinking, optimization, and obfuscation of Java class files. * * Copyright (c) 2002-2006 Eric Lafortune (eric@graphics.cornell.edu) * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */package proguard.obfuscate;import proguard.classfile.*;import proguard.classfile.attribute.*;import proguard.classfile.attribute.annotation.*;import proguard.classfile.visitor.*;/** * This ClassFileVisitor removes attributes that are not marked * as being used or required. * * @see AttributeUsageMarker * * @author Eric Lafortune */public class AttributeShrinker  implements ClassFileVisitor,             MemberInfoVisitor,             AttrInfoVisitor{    // Implementations for ClassFileVisitor.    public void visitProgramClassFile(ProgramClassFile programClassFile)    {        // Compact the array for class attributes.        programClassFile.u2attributesCount =            shrinkArray(programClassFile.attributes,                        programClassFile.u2attributesCount);        // Compact the attributes in fields, methods, and class attributes,        programClassFile.fieldsAccept(this);        programClassFile.methodsAccept(this);        programClassFile.attributesAccept(this);    }    public void visitLibraryClassFile(LibraryClassFile libraryClassFile)    {        // Library class files are left unchanged.    }    // Implementations for MemberInfoVisitor.    public void visitProgramFieldInfo(ProgramClassFile programClassFile, ProgramFieldInfo programFieldInfo)    {        visitMemberInfo(programClassFile, programFieldInfo);    }    public void visitProgramMethodInfo(ProgramClassFile programClassFile, ProgramMethodInfo programMethodInfo)    {        visitMemberInfo(programClassFile, programMethodInfo);    }    private void visitMemberInfo(ProgramClassFile programClassFile, ProgramMemberInfo programMemberInfo)    {        // Compact the attributes array.        programMemberInfo.u2attributesCount =            shrinkArray(programMemberInfo.attributes,                        programMemberInfo.u2attributesCount);        // Compact any attributes of the remaining attributes.        programMemberInfo.attributesAccept(programClassFile, this);    }    public void visitLibraryFieldInfo(LibraryClassFile libraryClassFile, LibraryFieldInfo libraryFieldInfo)    {        // Library class files are left unchanged.    }    public void visitLibraryMethodInfo(LibraryClassFile libraryClassFile, LibraryMethodInfo libraryMethodInfo)    {        // Library class files are left unchanged.    }    // Implementations for AttrInfoVisitor.    public void visitUnknownAttrInfo(ClassFile classFile, UnknownAttrInfo unknownAttrInfo) {}    public void visitInnerClassesAttrInfo(ClassFile classFile, InnerClassesAttrInfo innerClassesAttrInfo) {}    public void visitEnclosingMethodAttrInfo(ClassFile classFile, EnclosingMethodAttrInfo enclosingMethodAttrInfo) {}    public void visitConstantValueAttrInfo(ClassFile classFile, FieldInfo fieldInfo, ConstantValueAttrInfo constantValueAttrInfo) {}    public void visitExceptionsAttrInfo(ClassFile classFile, MethodInfo methodInfo, ExceptionsAttrInfo exceptionsAttrInfo) {}    public void visitLineNumberTableAttrInfo(ClassFile classFile, MethodInfo methodInfo, CodeAttrInfo codeAttrInfo, LineNumberTableAttrInfo lineNumberTableAttrInfo) {}    public void visitLocalVariableTableAttrInfo(ClassFile classFile, MethodInfo methodInfo, CodeAttrInfo codeAttrInfo, LocalVariableTableAttrInfo localVariableTableAttrInfo) {}    public void visitLocalVariableTypeTableAttrInfo(ClassFile classFile, MethodInfo methodInfo, CodeAttrInfo codeAttrInfo, LocalVariableTypeTableAttrInfo localVariableTypeTableAttrInfo) {}    public void visitSourceFileAttrInfo(ClassFile classFile, SourceFileAttrInfo sourceFileAttrInfo) {}    public void visitSourceDirAttrInfo(ClassFile classFile, SourceDirAttrInfo sourceDirAttrInfo) {}    public void visitDeprecatedAttrInfo(ClassFile classFile, DeprecatedAttrInfo deprecatedAttrInfo) {}    public void visitSyntheticAttrInfo(ClassFile classFile, SyntheticAttrInfo syntheticAttrInfo) {}    public void visitSignatureAttrInfo(ClassFile classFile, SignatureAttrInfo signatureAttrInfo) {}    public void visitRuntimeVisibleAnnotationAttrInfo(ClassFile classFile, RuntimeVisibleAnnotationsAttrInfo runtimeVisibleAnnotationsAttrInfo) {}    public void visitRuntimeInvisibleAnnotationAttrInfo(ClassFile classFile, RuntimeInvisibleAnnotationsAttrInfo runtimeInvisibleAnnotationsAttrInfo) {}    public void visitRuntimeVisibleParameterAnnotationAttrInfo(ClassFile classFile, RuntimeVisibleParameterAnnotationsAttrInfo runtimeVisibleParameterAnnotationsAttrInfo) {}    public void visitRuntimeInvisibleParameterAnnotationAttrInfo(ClassFile classFile, RuntimeInvisibleParameterAnnotationsAttrInfo runtimeInvisibleParameterAnnotationsAttrInfo) {}    public void visitAnnotationDefaultAttrInfo(ClassFile classFile, AnnotationDefaultAttrInfo annotationDefaultAttrInfo) {}    public void visitCodeAttrInfo(ClassFile classFile, MethodInfo methodInfo, CodeAttrInfo codeAttrInfo)    {        // Compact the attributes array.        codeAttrInfo.u2attributesCount =            shrinkArray(codeAttrInfo.attributes,                        codeAttrInfo.u2attributesCount);    }    // Small utility methods.    /**     * Removes all VisitorAccepter objects that are not marked as being used     * from the given array.     * @return the new number of VisitorAccepter objects.     */    private static int shrinkArray(VisitorAccepter[] array, int length)    {        int counter = 0;        // Shift the used objects together.        for (int index = 0; index < length; index++)        {            if (AttributeUsageMarker.isUsed(array[index]))            {                array[counter++] = array[index];            }        }        // Clear the remaining array elements.        for (int index = counter; index < length; index++)        {            array[index] = null;        }        return counter;    }}