@Override
  protected boolean preprocessUsages(@NotNull final Ref<UsageInfo[]> refUsages) {
    final MultiMap<PsiElement, String> conflicts = new MultiMap<PsiElement, String>();
    myExtractEnumProcessor.findEnumConstantConflicts(refUsages);
    if (!DestinationFolderComboBox.isAccessible(
        myProject,
        sourceClass.getContainingFile().getVirtualFile(),
        myClass.getContainingFile().getContainingDirectory().getVirtualFile())) {
      conflicts.putValue(
          sourceClass,
          "Extracted class won't be accessible in "
              + RefactoringUIUtil.getDescription(sourceClass, true));
    }
    ApplicationManager.getApplication()
        .runWriteAction(
            new Runnable() {
              public void run() {
                myClass.delete();
              }
            });
    final Project project = sourceClass.getProject();
    final GlobalSearchScope scope = GlobalSearchScope.allScope(project);
    final PsiClass existingClass =
        JavaPsiFacade.getInstance(project).findClass(getQualifiedName(), scope);
    if (existingClass != null) {
      conflicts.putValue(
          existingClass,
          RefactorJBundle.message("cannot.perform.the.refactoring")
              + RefactorJBundle.message("there.already.exists.a.class.with.the.chosen.name"));
    }

    if (!myGenerateAccessors) {
      calculateInitializersConflicts(conflicts);
      final NecessaryAccessorsVisitor visitor = checkNecessaryGettersSetters4ExtractedClass();
      final NecessaryAccessorsVisitor srcVisitor = checkNecessaryGettersSetters4SourceClass();
      final Set<PsiField> fieldsNeedingGetter = new LinkedHashSet<PsiField>();
      fieldsNeedingGetter.addAll(visitor.getFieldsNeedingGetter());
      fieldsNeedingGetter.addAll(srcVisitor.getFieldsNeedingGetter());
      for (PsiField field : fieldsNeedingGetter) {
        conflicts.putValue(field, "Field \'" + field.getName() + "\' needs getter");
      }
      final Set<PsiField> fieldsNeedingSetter = new LinkedHashSet<PsiField>();
      fieldsNeedingSetter.addAll(visitor.getFieldsNeedingSetter());
      fieldsNeedingSetter.addAll(srcVisitor.getFieldsNeedingSetter());
      for (PsiField field : fieldsNeedingSetter) {
        conflicts.putValue(field, "Field \'" + field.getName() + "\' needs setter");
      }
    }
    checkConflicts(refUsages, conflicts);
    return showConflicts(conflicts, refUsages.get());
  }
 public void findUsages(@NotNull List<FixableUsageInfo> usages) {
   for (PsiField field : fields) {
     findUsagesForField(field, usages);
     usages.add(new RemoveField(field));
   }
   usages.addAll(
       myExtractEnumProcessor.findEnumConstantUsages(new ArrayList<FixableUsageInfo>(usages)));
   for (PsiClass innerClass : innerClasses) {
     findUsagesForInnerClass(innerClass, usages);
     usages.add(new RemoveInnerClass(innerClass));
   }
   for (PsiMethod method : methods) {
     if (method.hasModifierProperty(PsiModifier.STATIC)) {
       findUsagesForStaticMethod(method, usages);
     } else {
       findUsagesForMethod(method, usages);
     }
   }
 }
  protected void performRefactoring(@NotNull UsageInfo[] usageInfos) {
    final PsiClass psiClass = buildClass();
    if (psiClass == null) return;
    if (delegationRequired) {
      buildDelegate();
    }
    myExtractEnumProcessor.performEnumConstantTypeMigration(usageInfos);
    final Set<PsiMember> members = new HashSet<PsiMember>();
    for (PsiMethod method : methods) {
      final PsiMethod member = psiClass.findMethodBySignature(method, false);
      if (member != null) {
        members.add(member);
      }
    }
    for (PsiField field : fields) {
      final PsiField member = psiClass.findFieldByName(field.getName(), false);
      if (member != null) {
        members.add(member);
        final PsiExpression initializer = member.getInitializer();
        if (initializer != null) {
          final boolean[] moveInitializerToConstructor = new boolean[1];
          initializer.accept(
              new JavaRecursiveElementWalkingVisitor() {
                @Override
                public void visitReferenceExpression(PsiReferenceExpression expression) {
                  super.visitReferenceExpression(expression);
                  final PsiElement resolved = expression.resolve();
                  if (resolved instanceof PsiField && !members.contains(resolved)) {
                    moveInitializerToConstructor[0] = true;
                  }
                }
              });

          if (moveInitializerToConstructor[0]) {
            final PsiElementFactory elementFactory = JavaPsiFacade.getElementFactory(myProject);
            PsiMethod[] constructors = psiClass.getConstructors();
            if (constructors.length == 0) {
              final PsiMethod constructor =
                  (PsiMethod) elementFactory.createConstructor().setName(psiClass.getName());
              constructors = new PsiMethod[] {(PsiMethod) psiClass.add(constructor)};
            }
            for (PsiMethod constructor : constructors) {
              MoveInstanceMembersUtil.moveInitializerToConstructor(
                  elementFactory, constructor, member);
            }
          }
        }
      }
    }

    if (myGenerateAccessors) {
      final NecessaryAccessorsVisitor visitor = checkNecessaryGettersSetters4SourceClass();
      for (PsiField field : visitor.getFieldsNeedingGetter()) {
        sourceClass.add(GenerateMembersUtil.generateGetterPrototype(field));
      }

      for (PsiField field : visitor.getFieldsNeedingSetter()) {
        sourceClass.add(GenerateMembersUtil.generateSetterPrototype(field));
      }
    }
    super.performRefactoring(usageInfos);
    if (myNewVisibility == null) return;
    for (PsiMember member : members) {
      VisibilityUtil.fixVisibility(UsageViewUtil.toElements(usageInfos), member, myNewVisibility);
    }
  }