/*
* ProGuard -- shrinking, optimization, obfuscation, and preverification
* of Java bytecode.
*
* Copyright (c) 2002-2011 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.optimize;
import proguard.classfile.*;
import proguard.classfile.editor.ClassReferenceFixer;
import proguard.classfile.util.*;
import proguard.classfile.visitor.MemberVisitor;
import proguard.evaluation.value.Value;
import proguard.optimize.evaluation.StoringInvocationUnit;
/**
* This MemberVisitor specializes parameters in the descriptors of the
* methods that it visits.
*
* @see StoringInvocationUnit
* @see ClassReferenceFixer
* @author Eric Lafortune
*/
public class MemberDescriptorSpecializer
extends SimplifiedVisitor
implements MemberVisitor
{
private static final boolean DEBUG = false;
private final MemberVisitor extraParameterMemberVisitor;
/**
* Creates a new MethodDescriptorShrinker.
*/
public MemberDescriptorSpecializer()
{
this(null);
}
/**
* Creates a new MethodDescriptorShrinker with an extra visitor.
* @param extraParameterMemberVisitor an optional extra visitor for all
* class members whose parameters have
* been specialized.
*/
public MemberDescriptorSpecializer(MemberVisitor extraParameterMemberVisitor)
{
this.extraParameterMemberVisitor = extraParameterMemberVisitor;
}
// Implementations for MemberVisitor.
public void visitProgramField(ProgramClass programClass, ProgramField programField)
{
Value parameterValue = StoringInvocationUnit.getFieldValue(programField);
if (parameterValue.computationalType() == Value.TYPE_REFERENCE)
{
Clazz referencedClass = parameterValue.referenceValue().getReferencedClass();
if (programField.referencedClass != referencedClass)
{
if (DEBUG)
{
System.out.println("MemberDescriptorSpecializer: "+programClass.getName()+"."+programField.getName(programClass)+" "+programField.getDescriptor(programClass));
System.out.println(" "+programField.referencedClass.getName()+" -> "+referencedClass.getName());
}
programField.referencedClass = referencedClass;
// Visit the field, if required.
if (extraParameterMemberVisitor != null)
{
extraParameterMemberVisitor.visitProgramField(programClass, programField);
}
}
}
}
public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod)
{
// All parameters of non-static methods are shifted by one in the local
// variable frame.
int firstParameterIndex =
(programMethod.getAccessFlags() & ClassConstants.INTERNAL_ACC_STATIC) != 0 ?
0 : 1;
int parameterCount =
ClassUtil.internalMethodParameterCount(programMethod.getDescriptor(programClass));
int classIndex = 0;
// Go over the parameters.
for (int parameterIndex = firstParameterIndex; parameterIndex < parameterCount; parameterIndex++)
{
Value parameterValue = StoringInvocationUnit.getMethodParameterValue(programMethod, parameterIndex);
if (parameterValue.computationalType() == Value.TYPE_REFERENCE)
{
Clazz referencedClass = parameterValue.referenceValue().getReferencedClass();
if (programMethod.referencedClasses[classIndex] != referencedClass)
{
if (DEBUG)
{
System.out.println("MemberDescriptorSpecializer: "+programClass.getName()+"."+programMethod.getName(programClass)+programMethod.getDescriptor(programClass));
System.out.println(" "+programMethod.referencedClasses[classIndex].getName()+" -> "+referencedClass.getName());
}
programMethod.referencedClasses[classIndex] = referencedClass;
// Visit the method, if required.
if (extraParameterMemberVisitor != null)
{
extraParameterMemberVisitor.visitProgramMethod(programClass, programMethod);
}
}
classIndex++;
}
}
}
}