/*
* 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.shrink;
import proguard.classfile.*;
import proguard.classfile.attribute.Attribute;
import proguard.classfile.attribute.annotation.*;
import proguard.classfile.attribute.annotation.visitor.*;
import proguard.classfile.attribute.visitor.AttributeVisitor;
import proguard.classfile.constant.*;
import proguard.classfile.constant.visitor.ConstantVisitor;
import proguard.classfile.util.SimplifiedVisitor;
import proguard.classfile.visitor.*;
/**
* This AttributeVisitor recursively marks all necessary annotation information
* in the attributes that it visits.
*
* @see UsageMarker
*
* @author Eric Lafortune
*/
public class AnnotationUsageMarker
extends SimplifiedVisitor
implements AttributeVisitor,
AnnotationVisitor,
ElementValueVisitor,
ConstantVisitor,
ClassVisitor,
MemberVisitor
{
private final UsageMarker usageMarker;
// Fields acting as a return parameters for several methods.
private boolean attributeUsed;
private boolean annotationUsed;
private boolean classUsed;
private boolean methodUsed;
/**
* Creates a new AnnotationUsageMarker.
* @param usageMarker the usage marker that is used to mark the classes
* and class members.
*/
public AnnotationUsageMarker(UsageMarker usageMarker)
{
this.usageMarker = usageMarker;
}
// Implementations for AttributeVisitor.
public void visitAnyAttribute(Clazz clazz, Attribute attribute) {}
public void visitAnyAnnotationsAttribute(Clazz clazz, AnnotationsAttribute annotationsAttribute)
{
// Mark the necessary annotation information.
attributeUsed = false;
annotationsAttribute.annotationsAccept(clazz, this);
if (attributeUsed)
{
// We got a positive used flag, so some annotation is being used.
// Mark this attribute as being used as well.
usageMarker.markAsUsed(annotationsAttribute);
markConstant(clazz, annotationsAttribute.u2attributeNameIndex);
}
}
public void visitAnyParameterAnnotationsAttribute(Clazz clazz, Method method, ParameterAnnotationsAttribute parameterAnnotationsAttribute)
{
// Mark the necessary annotation information.
attributeUsed = false;
parameterAnnotationsAttribute.annotationsAccept(clazz, method, this);
if (attributeUsed)
{
// We got a positive used flag, so some annotation is being used.
// Mark this attribute as being used as well.
usageMarker.markAsUsed(parameterAnnotationsAttribute);
markConstant(clazz, parameterAnnotationsAttribute.u2attributeNameIndex);
}
}
public void visitAnnotationDefaultAttribute(Clazz clazz, Method method, AnnotationDefaultAttribute annotationDefaultAttribute)
{
// Mark the necessary annotation information in any annotation elements.
annotationDefaultAttribute.defaultValueAccept(clazz, this);
// Always mark annotation defaults.
usageMarker.markAsUsed(annotationDefaultAttribute);
markConstant(clazz, annotationDefaultAttribute.u2attributeNameIndex);
}
// Implementations for AnnotationVisitor.
public void visitAnnotation(Clazz clazz, Annotation annotation)
{
if (isReferencedClassUsed(annotation))
{
// Mark the annotation as being used.
usageMarker.markAsUsed(annotation);
markConstant(clazz, annotation.u2typeIndex);
// Mark the necessary element values.
annotation.elementValuesAccept(clazz, this);
// The return values.
annotationUsed = true;
attributeUsed = true;
}
}
// Implementations for ElementValueVisitor.
public void visitConstantElementValue(Clazz clazz, Annotation annotation, ConstantElementValue constantElementValue)
{
if (isReferencedMethodUsed(constantElementValue))
{
// Mark the element value as being used.
usageMarker.markAsUsed(constantElementValue);
markConstant(clazz, constantElementValue.u2elementNameIndex);
markConstant(clazz, constantElementValue.u2constantValueIndex);
}
}
public void visitEnumConstantElementValue(Clazz clazz, Annotation annotation, EnumConstantElementValue enumConstantElementValue)
{
if (isReferencedMethodUsed(enumConstantElementValue))
{
// Check the referenced classes.
classUsed = true;
enumConstantElementValue.referencedClassesAccept(this);
if (classUsed)
{
// Mark the element value as being used.
usageMarker.markAsUsed(enumConstantElementValue);
markConstant(clazz, enumConstantElementValue.u2elementNameIndex);
markConstant(clazz, enumConstantElementValue.u2typeNameIndex);
markConstant(clazz, enumConstantElementValue.u2constantNameIndex);
}
}
}
public void visitClassElementValue(Clazz clazz, Annotation annotation, ClassElementValue classElementValue)
{
if (isReferencedMethodUsed(classElementValue))
{
// Check the referenced classes.
classUsed = true;
classElementValue.referencedClassesAccept(this);
if (classUsed)
{
// Mark the element value as being used.
usageMarker.markAsUsed(classElementValue);
markConstant(clazz, classElementValue.u2elementNameIndex);
markConstant(clazz, classElementValue.u2classInfoIndex);
}
}
}
public void visitAnnotationElementValue(Clazz clazz, Annotation annotation, AnnotationElementValue annotationElementValue)
{
if (isReferencedMethodUsed(annotationElementValue))
{
boolean oldAnnotationUsed = annotationUsed;
// Check and mark the contained annotation.
annotationUsed = false;
annotationElementValue.annotationAccept(clazz, this);
if (annotationUsed)
{
// Mark the element value as being used.
usageMarker.markAsUsed(annotationElementValue);
markConstant(clazz, annotationElementValue.u2elementNameIndex);
}
annotationUsed = oldAnnotationUsed;
}
}
public void visitArrayElementValue(Clazz clazz, Annotation annotation, ArrayElementValue arrayElementValue)
{
if (isReferencedMethodUsed(arrayElementValue))
{
// Check and mark the contained element values.
arrayElementValue.elementValuesAccept(clazz, annotation, this);
// Mark the element value as being used.
usageMarker.markAsUsed(arrayElementValue);
markConstant(clazz, arrayElementValue.u2elementNameIndex);
}
}
// Implementations for ConstantVisitor.
public void visitAnyConstant(Clazz clazz, Constant constant)
{
usageMarker.markAsUsed(constant);
}
public void visitClassConstant(Clazz clazz, ClassConstant classConstant)
{
classUsed = usageMarker.isUsed(classConstant);
// Is the class constant marked as being used?
if (!classUsed)
{
// Check the referenced class.
classUsed = true;
classConstant.referencedClassAccept(this);
// Is the referenced class marked as being used?
if (classUsed)
{
// Mark the class constant and its Utf8 constant.
usageMarker.markAsUsed(classConstant);
markConstant(clazz, classConstant.u2nameIndex);
}
}
}
// Implementations for ClassVisitor.
public void visitProgramClass(ProgramClass programClass)
{
classUsed = usageMarker.isUsed(programClass);
}
public void visitLibraryClass(LibraryClass libraryClass)
{
classUsed = true;
}
// Implementations for MemberVisitor.
public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod)
{
methodUsed = usageMarker.isUsed(programMethod);
}
public void visitLibraryMethod(LibraryClass LibraryClass, LibraryMethod libraryMethod)
{
classUsed = true;
}
// Small utility methods.
/**
* Returns whether the annotation class has been marked as being used.
*/
private boolean isReferencedClassUsed(Annotation annotation)
{
// Check if the referenced class is being used.
classUsed = true;
annotation.referencedClassAccept(this);
return classUsed;
}
/**
* Returns whether the annotation method has been marked as being used.
*/
private boolean isReferencedMethodUsed(ElementValue elementValue)
{
// Check if the referenced method is being used.
methodUsed = true;
elementValue.referencedMethodAccept(this);
return methodUsed;
}
/**
* Marks the specified constant pool entry.
*/
private void markConstant(Clazz clazz, int index)
{
if (index > 0)
{
clazz.constantPoolEntryAccept(index, this);
}
}
}