classfileaccessfilter.java

j2me 混淆包,用于混淆j2me的原代码用的

/* $Id: ClassFileAccessFilter.java,v 1.6 2004/12/11 16:35:23 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.classfile.visitor;

import proguard.classfile.*;


/**
 * This <code>ClassFileVisitor</code> delegates its visits to another given
 * <code>ClassFileVisitor</code>, but only when the visited class file
 * has the proper access flags.
 *
 * @see ClassConstants
 *
 * @author Eric Lafortune
 */
public class ClassFileAccessFilter implements ClassFileVisitor
{
    private int              requiredSetAccessFlags;
    private int              requiredUnsetAccessFlags;
    private ClassFileVisitor classFileVisitor;


    /**
     * Creates a new ClassFileAccessFilter.
     * @param requiredSetAccessFlags   the class access flags that should be
     *                                 set.
     * @param requiredUnsetAccessFlags the class access flags that should be
     *                                 unset.
     * @param classFileVisitor         the <code>ClassFileVisitor</code> to
     *                                 which visits will be delegated.
     */
    public ClassFileAccessFilter(int              requiredSetAccessFlags,
                                 int              requiredUnsetAccessFlags,
                                 ClassFileVisitor classFileVisitor)
    {
        this.requiredSetAccessFlags   = requiredSetAccessFlags;
        this.requiredUnsetAccessFlags = requiredUnsetAccessFlags;
        this.classFileVisitor         = classFileVisitor;
    }


    // Implementations for ClassFileVisitor.

    public void visitProgramClassFile(ProgramClassFile programClassFile)
    {
        if (accepted(programClassFile.getAccessFlags()))
        {
            classFileVisitor.visitProgramClassFile(programClassFile);
        }
    }


    public void visitLibraryClassFile(LibraryClassFile libraryClassFile)
    {
        if (accepted(libraryClassFile.getAccessFlags()))
        {
            classFileVisitor.visitLibraryClassFile(libraryClassFile);
        }
    }


    // Small utility methods.

    private boolean accepted(int accessFlags)
    {
        return (requiredSetAccessFlags   & ~accessFlags) == 0 &&
               (requiredUnsetAccessFlags &  accessFlags) == 0;
    }
}