nameandtypeusagemarker.java

j2me 混淆包,用于混淆j2me的原代码用的

/* $Id: NameAndTypeUsageMarker.java,v 1.13 2004/11/26 12:46:43 eric Exp $
 *
 * ProGuard -- shrinking, optimization, and obfuscation of Java class files.
 *
 * Copyright (c) 2002-2004 Eric Lafortune ([e-mail])
 *
 * 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 marks all NameAndType constant pool entries that are
 * being used in the classes it visits.
 *
 * @see NameAndTypeShrinker
 *
 * @author Eric Lafortune
 */
public class NameAndTypeUsageMarker
  implements ClassFileVisitor,
             CpInfoVisitor,
             AttrInfoVisitor
{
    // A visitor info flag to indicate the NameAndType constant pool entry is being used.
    private static final Object USED = new Object();


    // Implementations for ClassFileVisitor.

    public void visitProgramClassFile(ProgramClassFile programClassFile)
    {
        // Mark the NameAndType entries referenced by all other constant pool
        // entries.
        programClassFile.constantPoolEntriesAccept(this);

        // Mark the NameAndType entries referenced by all EnclosingMethod
        // attributes.
        programClassFile.attributesAccept(this);
    }


    public void visitLibraryClassFile(LibraryClassFile libraryClassFile)
    {
    }


    // Implementations for CpInfoVisitor.

    public void visitIntegerCpInfo(ClassFile classFile, IntegerCpInfo integerCpInfo) {}
    public void visitLongCpInfo(ClassFile classFile, LongCpInfo longCpInfo) {}
    public void visitFloatCpInfo(ClassFile classFile, FloatCpInfo floatCpInfo) {}
    public void visitDoubleCpInfo(ClassFile classFile, DoubleCpInfo doubleCpInfo) {}
    public void visitUtf8CpInfo(ClassFile classFile, Utf8CpInfo utf8CpInfo) {}
    public void visitStringCpInfo(ClassFile classFile, StringCpInfo stringCpInfo) {}
    public void visitClassCpInfo(ClassFile classFile, ClassCpInfo classCpInfo) {}
    public void visitNameAndTypeCpInfo(ClassFile classFile, NameAndTypeCpInfo nameAndTypeCpInfo) {}


    public void visitFieldrefCpInfo(ClassFile classFile, FieldrefCpInfo fieldrefCpInfo)
    {
        visitRefCpInfo(classFile, fieldrefCpInfo);
    }


    public void visitInterfaceMethodrefCpInfo(ClassFile classFile, InterfaceMethodrefCpInfo interfaceMethodrefCpInfo)
    {
        visitRefCpInfo(classFile, interfaceMethodrefCpInfo);
    }


    public void visitMethodrefCpInfo(ClassFile classFile, MethodrefCpInfo methodrefCpInfo)
    {
        visitRefCpInfo(classFile, methodrefCpInfo);
    }


    private void visitRefCpInfo(ClassFile classFile, RefCpInfo refCpInfo)
    {
        markNameAndTypeCpEntry(classFile, refCpInfo.u2nameAndTypeIndex);
    }


    // Implementations for AttrInfoVisitor.

    public void visitUnknownAttrInfo(ClassFile classFile, UnknownAttrInfo unknownAttrInfo) {}
    public void visitInnerClassesAttrInfo(ClassFile classFile, InnerClassesAttrInfo innerClassesAttrInfo) {}
    public void visitConstantValueAttrInfo(ClassFile classFile, FieldInfo fieldInfo, ConstantValueAttrInfo constantValueAttrInfo) {}
    public void visitExceptionsAttrInfo(ClassFile classFile, MethodInfo methodInfo, ExceptionsAttrInfo exceptionsAttrInfo) {}
    public void visitCodeAttrInfo(ClassFile classFile, MethodInfo methodInfo, CodeAttrInfo codeAttrInfo) {}
    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 visitEnclosingMethodAttrInfo(ClassFile classFile, EnclosingMethodAttrInfo enclosingMethodAttrInfo)
    {
        if (enclosingMethodAttrInfo.u2nameAndTypeIndex != 0)
        {
            markNameAndTypeCpEntry(classFile, enclosingMethodAttrInfo.u2nameAndTypeIndex);
        }
    }


    // Small utility methods.

    /**
     * Marks the given UTF-8 constant pool entry of the given class.
     */
    private void markNameAndTypeCpEntry(ClassFile classFile, int index)
    {
         markAsUsed((NameAndTypeCpInfo)((ProgramClassFile)classFile).getCpEntry(index));
    }


    /**
     * Marks the given VisitorAccepter as being used.
     * In this context, the VisitorAccepter will be a NameAndTypeCpInfo object.
     */
    private static void markAsUsed(VisitorAccepter visitorAccepter)
    {
        visitorAccepter.setVisitorInfo(USED);
    }


    /**
     * Returns whether the given VisitorAccepter has been marked as being used.
     * In this context, the VisitorAccepter will be a NameAndTypeCpInfo object.
     */
    static boolean isUsed(VisitorAccepter visitorAccepter)
    {
        return visitorAccepter.getVisitorInfo() == USED;
    }
}