memberreferencefixer.java

ProGuard 是一个免费的 Java类文件的压缩

            isInterfaceMethod = false;
            clazz.constantPoolEntryAccept(methodrefConstant.u2classIndex, this);

            // Has the method become an interface method?
            if (isInterfaceMethod)
            {
                if (DEBUG)
                {
                    System.out.println("MemberReferenceFixer:");
                    System.out.println("  Class file     = "+clazz.getName());
                    System.out.println("  Ref class      = "+referencedClass.getName());
                    System.out.println("  Ref method     = "+methodrefConstant.getName(clazz)+methodrefConstant.getType(clazz));
                    System.out.println("    -> interface method");
                }

                // Replace the method reference by an interface method reference.
                ((ProgramClass)clazz).constantPool[this.constantIndex] =
                    new InterfaceMethodrefConstant(methodrefConstant.u2classIndex,
                                                   methodrefConstant.u2nameAndTypeIndex,
                                                   referencedClass,
                                                   referencedMember);
            }
        }
    }


    public void visitClassConstant(Clazz clazz, ClassConstant classConstant)
    {
        // Check if this class entry is an array type.
        if (ClassUtil.isInternalArrayType(classConstant.getName(clazz)))
        {
            isInterfaceMethod = false;
        }
        else
        {
            // Check if this class entry refers to an interface class.
            Clazz referencedClass = classConstant.referencedClass;
            if (referencedClass != null)
            {
                isInterfaceMethod = (referencedClass.getAccessFlags() & ClassConstants.INTERNAL_ACC_INTERFACE) != 0;
            }
        }
    }


    // Implementations for MemberVisitor.

    public void visitProgramMember(ProgramClass programClass, ProgramMember programMember)
    {
        // Fix the attributes.
        programMember.attributesAccept(programClass, this);
    }


    // Implementations for AttributeVisitor.

    public void visitAnyAttribute(Clazz clazz, Attribute attribute) {}


    public void visitEnclosingMethodAttribute(Clazz clazz, EnclosingMethodAttribute enclosingMethodAttribute)
    {
        Member referencedMember = enclosingMethodAttribute.referencedMethod;
        if (referencedMember != null)
        {
            Clazz referencedClass = enclosingMethodAttribute.referencedClass;

            // Does it have a new class?
            if (!enclosingMethodAttribute.getClassName(clazz).equals(referencedClass.getName()))
            {
                // Update the class index.
                enclosingMethodAttribute.u2classIndex =
                    constantPoolEditor.addClassConstant((ProgramClass)clazz,
                                                        referencedClass);
            }

            // Does it have a new name or type?
            if (!enclosingMethodAttribute.getName(clazz).equals(referencedMember.getName(referencedClass)) ||
                !enclosingMethodAttribute.getType(clazz).equals(referencedMember.getDescriptor(referencedClass)))
            {
                // Update the name and type index.
                enclosingMethodAttribute.u2nameAndTypeIndex =
                    constantPoolEditor.addNameAndTypeConstant((ProgramClass)clazz,
                                                              referencedMember.getName(referencedClass),
                                                              referencedMember.getDescriptor(referencedClass));
            }
        }
    }


    public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute)
    {
        // Recompute the maximum stack size if necessary.
        if (stackSizesMayHaveChanged)
        {
            stackSizeUpdater.visitCodeAttribute(clazz, method, codeAttribute);
        }

        // Fix the nested attributes.
        codeAttribute.attributesAccept(clazz, method, this);
    }


    public void visitAnyAnnotationsAttribute(Clazz clazz, AnnotationsAttribute annotationsAttribute)
    {
        // Fix the annotations.
        annotationsAttribute.annotationsAccept(clazz, this);
    }


    public void visitAnyParameterAnnotationsAttribute(Clazz clazz, Method method, ParameterAnnotationsAttribute parameterAnnotationsAttribute)
    {
        // Fix the annotations.
        parameterAnnotationsAttribute.annotationsAccept(clazz, method, this);
    }


    public void visitAnnotationDefaultAttribute(Clazz clazz, Method method, AnnotationDefaultAttribute annotationDefaultAttribute)
    {
        // Fix the annotation.
        annotationDefaultAttribute.defaultValueAccept(clazz, this);
    }


    // Implementations for AnnotationVisitor.

    public void visitAnnotation(Clazz clazz, Annotation annotation)
    {
        // Fix the element values.
        annotation.elementValuesAccept(clazz, this);
    }


    // Implementations for ElementValueVisitor.

    public void visitConstantElementValue(Clazz clazz, Annotation annotation, ConstantElementValue constantElementValue)
    {
        fixElementValue(clazz, annotation, constantElementValue);
    }


    public void visitEnumConstantElementValue(Clazz clazz, Annotation annotation, EnumConstantElementValue enumConstantElementValue)
    {
        fixElementValue(clazz, annotation, enumConstantElementValue);
    }


    public void visitClassElementValue(Clazz clazz, Annotation annotation, ClassElementValue classElementValue)
    {
        fixElementValue(clazz, annotation, classElementValue);
    }


    public void visitAnnotationElementValue(Clazz clazz, Annotation annotation, AnnotationElementValue annotationElementValue)
    {
        fixElementValue(clazz, annotation, annotationElementValue);

        // Fix the annotation.
        annotationElementValue.annotationAccept(clazz, this);
    }


    public void visitArrayElementValue(Clazz clazz, Annotation annotation, ArrayElementValue arrayElementValue)
    {
        fixElementValue(clazz, annotation, arrayElementValue);

        // Fix the element values.
        arrayElementValue.elementValuesAccept(clazz, annotation, this);
    }


    // Small utility methods.

    /**
     * Fixes the method reference of the element value, if any.
     */
    private void fixElementValue(Clazz        clazz,
                                 Annotation   annotation,
                                 ElementValue elementValue)
    {
        // Do we know the referenced method?
        Member referencedMember = elementValue.referencedMethod;
        if (referencedMember != null)
        {
            // Does it have a new name or type?
            String methodName    = elementValue.getMethodName(clazz);
            String newMethodName = referencedMember.getName(elementValue.referencedClass);

            if (!methodName.equals(newMethodName))
            {
                // Update the element name index.
                elementValue.u2elementNameIndex =
                    constantPoolEditor.addUtf8Constant((ProgramClass)clazz,
                                                       newMethodName);
            }
        }
    }


    private void debug(Clazz       clazz,
                       RefConstant refConstant,
                       Clazz       referencedClass,
                       Member      referencedMember)
    {
        System.out.println("MemberReferenceFixer:");
        System.out.println("  Class file      = "+clazz.getName());
        System.out.println("  Ref class       = "+referencedClass.getName());
        System.out.println("  Ref member name = "+refConstant.getName(clazz));
        System.out.println("                 -> "+referencedMember.getName(referencedClass));
        System.out.println("  Ref descriptor  = "+refConstant.getType(clazz));
        System.out.println("                 -> "+referencedMember.getDescriptor(referencedClass));
    }
}