@Nullable
 private CommonProblemDescriptor[] checkElement(
     RefClass refEntity, InspectionManager manager, final Project project) {
   final PsiClass psiClass = refEntity.getElement();
   if (psiClass == null) return null;
   return checkElement(psiClass, manager, project);
 }
 @Override
 public void onInitialize(RefElement refElement) {
   ((RefElementImpl) refElement).setFlag(true, CAN_BE_FINAL_MASK);
   if (refElement instanceof RefClass) {
     final RefClass refClass = (RefClass) refElement;
     final PsiClass psiClass = refClass.getElement();
     if (refClass.isEntry()) {
       ((RefClassImpl) refClass).setFlag(false, CAN_BE_FINAL_MASK);
       return;
     }
     if (refClass.isAbstract() || refClass.isAnonymous() || refClass.isInterface()) {
       ((RefClassImpl) refClass).setFlag(false, CAN_BE_FINAL_MASK);
       return;
     }
     if (!refClass.isSelfInheritor(psiClass)) {
       for (PsiClass psiSuperClass : psiClass.getSupers()) {
         if (myManager.belongsToScope(psiSuperClass)) {
           RefClass refSuperClass = (RefClass) myManager.getReference(psiSuperClass);
           if (refSuperClass != null) {
             ((RefClassImpl) refSuperClass).setFlag(false, CAN_BE_FINAL_MASK);
           }
         }
       }
     }
   } else if (refElement instanceof RefMethod) {
     final RefMethod refMethod = (RefMethod) refElement;
     final PsiElement element = refMethod.getElement();
     if (element instanceof PsiMethod) {
       PsiMethod psiMethod = (PsiMethod) element;
       if (refMethod.isConstructor()
           || refMethod.isAbstract()
           || refMethod.isStatic()
           || PsiModifier.PRIVATE.equals(refMethod.getAccessModifier())
           || refMethod.getOwnerClass().isAnonymous()
           || refMethod.getOwnerClass().isInterface()) {
         ((RefMethodImpl) refMethod).setFlag(false, CAN_BE_FINAL_MASK);
       }
       if (PsiModifier.PRIVATE.equals(refMethod.getAccessModifier())
           && refMethod.getOwner() != null
           && !(refMethod.getOwnerClass().getOwner() instanceof RefElement)) {
         ((RefMethodImpl) refMethod).setFlag(false, CAN_BE_FINAL_MASK);
       }
       for (PsiMethod psiSuperMethod : psiMethod.findSuperMethods()) {
         if (myManager.belongsToScope(psiSuperMethod)) {
           RefMethod refSuperMethod = (RefMethod) myManager.getReference(psiSuperMethod);
           if (refSuperMethod != null) {
             ((RefMethodImpl) refSuperMethod).setFlag(false, CAN_BE_FINAL_MASK);
           }
         }
       }
     }
   }
 }
  private boolean isAccessibleFrom(RefElement from, RefJavaElement to, String accessModifier) {
    if (accessModifier == PsiModifier.PUBLIC) return true;

    final RefJavaUtil refUtil = RefJavaUtil.getInstance();
    if (accessModifier == PsiModifier.PACKAGE_LOCAL) {
      return RefJavaUtil.getPackage(from) == RefJavaUtil.getPackage(to);
    }

    RefClass fromTopLevel = refUtil.getTopLevelClass(from);
    RefClass toTopLevel = refUtil.getTopLevelClass(to);
    RefClass fromOwner = refUtil.getOwnerClass(from);
    RefClass toOwner = refUtil.getOwnerClass(to);

    if (accessModifier == PsiModifier.PROTECTED) {
      if (SUGGEST_PRIVATE_FOR_INNERS) {
        return refUtil.isInheritor(fromTopLevel, toOwner)
            || fromOwner != null && refUtil.isInheritor(fromOwner, toTopLevel)
            || toOwner != null && refUtil.getOwnerClass(toOwner) == from;
      }

      return refUtil.isInheritor(fromTopLevel, toOwner);
    }

    if (accessModifier == PsiModifier.PRIVATE) {
      if (SUGGEST_PRIVATE_FOR_INNERS) {
        if (isInExtendsList(to, fromTopLevel.getElement().getExtendsList())) return false;
        if (isInExtendsList(to, fromTopLevel.getElement().getImplementsList())) return false;
        if (isInAnnotations(to, fromTopLevel)) return false;
        return fromTopLevel == toOwner
            || fromOwner == toTopLevel
            || toOwner != null && refUtil.getOwnerClass(toOwner) == from;
      }

      if (fromOwner != null
          && fromOwner.isStatic()
          && !to.isStatic()
          && refUtil.isInheritor(fromOwner, toOwner)) return false;

      if (fromTopLevel == toOwner) {
        if (from instanceof RefClass && to instanceof RefClass) {
          final PsiClass fromClass = ((RefClass) from).getElement();
          LOG.assertTrue(fromClass != null);
          if (isInExtendsList(to, fromClass.getExtendsList())) return false;
          if (isInExtendsList(to, fromClass.getImplementsList())) return false;
        }

        return true;
      }
    }

    return false;
  }
  private static boolean isInAnnotations(final RefJavaElement to, final RefClass fromTopLevel) {
    final PsiModifierList modifierList = fromTopLevel.getElement().getModifierList();
    if (modifierList == null) return false;
    final PsiElement toElement = to.getElement();

    final boolean[] resolved = new boolean[] {false};
    modifierList.accept(
        new JavaRecursiveElementWalkingVisitor() {
          @Override
          public void visitReferenceExpression(PsiReferenceExpression expression) {
            if (resolved[0]) return;
            super.visitReferenceExpression(expression);
            if (expression.resolve() == toElement) {
              resolved[0] = true;
            }
          }
        });
    return resolved[0];
  }