@NotNull
  private static PsiClass[] getSupersInner(@NotNull PsiClass psiClass) {
    PsiClassType[] extendsListTypes = psiClass.getExtendsListTypes();
    PsiClassType[] implementsListTypes = psiClass.getImplementsListTypes();

    if (psiClass.isInterface()) {
      return resolveClassReferenceList(
          extendsListTypes, psiClass.getManager(), psiClass.getResolveScope(), true);
    }

    if (psiClass instanceof PsiAnonymousClass) {
      PsiAnonymousClass psiAnonymousClass = (PsiAnonymousClass) psiClass;
      PsiClassType baseClassReference = psiAnonymousClass.getBaseClassType();
      PsiClass baseClass = baseClassReference.resolve();
      if (baseClass != null) {
        if (baseClass.isInterface()) {
          PsiClass objectClass =
              JavaPsiFacade.getInstance(psiClass.getProject())
                  .findClass(CommonClassNames.JAVA_LANG_OBJECT, psiClass.getResolveScope());
          return objectClass != null
              ? new PsiClass[] {objectClass, baseClass}
              : new PsiClass[] {baseClass};
        }
        return new PsiClass[] {baseClass};
      }

      PsiClass objectClass =
          JavaPsiFacade.getInstance(psiClass.getProject())
              .findClass(CommonClassNames.JAVA_LANG_OBJECT, psiClass.getResolveScope());
      return objectClass != null ? new PsiClass[] {objectClass} : PsiClass.EMPTY_ARRAY;
    }
    if (psiClass instanceof PsiTypeParameter) {
      if (extendsListTypes.length == 0) {
        final PsiClass objectClass =
            JavaPsiFacade.getInstance(psiClass.getProject())
                .findClass(CommonClassNames.JAVA_LANG_OBJECT, psiClass.getResolveScope());
        return objectClass != null ? new PsiClass[] {objectClass} : PsiClass.EMPTY_ARRAY;
      }
      return resolveClassReferenceList(
          extendsListTypes, psiClass.getManager(), psiClass.getResolveScope(), false);
    }

    PsiClass[] interfaces =
        resolveClassReferenceList(
            implementsListTypes, psiClass.getManager(), psiClass.getResolveScope(), false);

    PsiClass superClass = getSuperClass(psiClass);
    if (superClass == null) return interfaces;
    PsiClass[] types = new PsiClass[interfaces.length + 1];
    types[0] = superClass;
    System.arraycopy(interfaces, 0, types, 1, interfaces.length);

    return types;
  }
  @Nullable
  public static PsiClass getSuperClass(@NotNull PsiClass psiClass) {
    PsiManager manager = psiClass.getManager();
    GlobalSearchScope resolveScope = psiClass.getResolveScope();

    final JavaPsiFacade facade = JavaPsiFacade.getInstance(manager.getProject());
    if (psiClass.isInterface()) {
      return facade.findClass(CommonClassNames.JAVA_LANG_OBJECT, resolveScope);
    }
    if (psiClass.isEnum()) {
      return facade.findClass(CommonClassNames.JAVA_LANG_ENUM, resolveScope);
    }

    if (psiClass instanceof PsiAnonymousClass) {
      PsiClassType baseClassReference = ((PsiAnonymousClass) psiClass).getBaseClassType();
      PsiClass baseClass = baseClassReference.resolve();
      if (baseClass == null || baseClass.isInterface())
        return facade.findClass(CommonClassNames.JAVA_LANG_OBJECT, resolveScope);
      return baseClass;
    }

    if (CommonClassNames.JAVA_LANG_OBJECT.equals(psiClass.getQualifiedName())) return null;

    final PsiClassType[] referenceElements = psiClass.getExtendsListTypes();

    if (referenceElements.length == 0)
      return facade.findClass(CommonClassNames.JAVA_LANG_OBJECT, resolveScope);

    PsiClass psiResoved = referenceElements[0].resolve();
    return psiResoved == null
        ? facade.findClass(CommonClassNames.JAVA_LANG_OBJECT, resolveScope)
        : psiResoved;
  }
  public static boolean isClassEquivalentTo(@NotNull PsiClass aClass, PsiElement another) {
    if (aClass == another) return true;
    if (!(another instanceof PsiClass)) return false;
    String name1 = aClass.getName();
    if (name1 == null) return false;
    if (!another.isValid()) return false;
    String name2 = ((PsiClass) another).getName();
    if (name2 == null) return false;
    if (name1.hashCode() != name2.hashCode()) return false;
    if (!name1.equals(name2)) return false;
    String qName1 = aClass.getQualifiedName();
    String qName2 = ((PsiClass) another).getQualifiedName();
    if (qName1 == null || qName2 == null) {
      //noinspection StringEquality
      if (qName1 != qName2) return false;

      if (aClass instanceof PsiTypeParameter && another instanceof PsiTypeParameter) {
        PsiTypeParameter p1 = (PsiTypeParameter) aClass;
        PsiTypeParameter p2 = (PsiTypeParameter) another;

        return p1.getIndex() == p2.getIndex()
            && aClass.getManager().areElementsEquivalent(p1.getOwner(), p2.getOwner());
      } else {
        return false;
      }
    }
    if (qName1.hashCode() != qName2.hashCode() || !qName1.equals(qName2)) {
      return false;
    }

    if (originalElement(aClass).equals(originalElement((PsiClass) another))) {
      return true;
    }

    final PsiFile file1 = aClass.getContainingFile().getOriginalFile();
    final PsiFile file2 = another.getContainingFile().getOriginalFile();

    // see com.intellij.openapi.vcs.changes.PsiChangeTracker
    // see com.intellij.psi.impl.PsiFileFactoryImpl#createFileFromText(CharSequence,PsiFile)
    final PsiFile original1 = file1.getUserData(PsiFileFactory.ORIGINAL_FILE);
    final PsiFile original2 = file2.getUserData(PsiFileFactory.ORIGINAL_FILE);
    if (original1 == original2 && original1 != null
        || original1 == file2
        || original2 == file1
        || file1 == file2) {
      return compareClassSeqNumber(aClass, (PsiClass) another);
    }

    final FileIndexFacade fileIndex =
        ServiceManager.getService(file1.getProject(), FileIndexFacade.class);
    final VirtualFile vfile1 = file1.getViewProvider().getVirtualFile();
    final VirtualFile vfile2 = file2.getViewProvider().getVirtualFile();
    boolean lib1 = fileIndex.isInLibraryClasses(vfile1);
    boolean lib2 = fileIndex.isInLibraryClasses(vfile2);

    return (fileIndex.isInSource(vfile1) || lib1) && (fileIndex.isInSource(vfile2) || lib2);
  }
  @NotNull
  public static PsiClass[] getInterfaces(@NotNull PsiClass psiClass) {
    if (psiClass.isInterface()) {
      final PsiClassType[] extendsListTypes = psiClass.getExtendsListTypes();
      return resolveClassReferenceList(
          extendsListTypes, psiClass.getManager(), psiClass.getResolveScope(), false);
    }

    if (psiClass instanceof PsiAnonymousClass) {
      PsiClassType baseClassReference = ((PsiAnonymousClass) psiClass).getBaseClassType();
      PsiClass baseClass = baseClassReference.resolve();
      return baseClass != null && baseClass.isInterface()
          ? new PsiClass[] {baseClass}
          : PsiClass.EMPTY_ARRAY;
    }

    final PsiClassType[] implementsListTypes = psiClass.getImplementsListTypes();
    return resolveClassReferenceList(
        implementsListTypes, psiClass.getManager(), psiClass.getResolveScope(), false);
  }
  @NotNull
  public static PsiClassType[] getSuperTypes(@NotNull PsiClass psiClass) {
    if (psiClass instanceof PsiAnonymousClass) {
      PsiClassType baseClassType = ((PsiAnonymousClass) psiClass).getBaseClassType();
      PsiClass baseClass = baseClassType.resolve();
      if (baseClass == null || !baseClass.isInterface()) {
        return new PsiClassType[] {baseClassType};
      } else {
        PsiClassType objectType =
            PsiType.getJavaLangObject(psiClass.getManager(), psiClass.getResolveScope());
        return new PsiClassType[] {objectType, baseClassType};
      }
    }

    PsiClassType[] extendsTypes = psiClass.getExtendsListTypes();
    PsiClassType[] implementsTypes = psiClass.getImplementsListTypes();
    boolean hasExtends = extendsTypes.length != 0;
    int extendsListLength = extendsTypes.length + (hasExtends ? 0 : 1);
    PsiClassType[] result = new PsiClassType[extendsListLength + implementsTypes.length];

    System.arraycopy(extendsTypes, 0, result, 0, extendsTypes.length);
    if (!hasExtends) {
      if (CommonClassNames.JAVA_LANG_OBJECT.equals(psiClass.getQualifiedName())) {
        return PsiClassType.EMPTY_ARRAY;
      }
      PsiManager manager = psiClass.getManager();
      PsiClassType objectType = PsiType.getJavaLangObject(manager, psiClass.getResolveScope());
      result[0] = objectType;
    }
    System.arraycopy(implementsTypes, 0, result, extendsListLength, implementsTypes.length);
    for (int i = 0; i < result.length; i++) {
      PsiClassType type = result[i];
      result[i] = (PsiClassType) PsiUtil.captureToplevelWildcards(type, psiClass);
    }
    return result;
  }
 private static PsiClassType getEnumSuperType(
     @NotNull PsiClass psiClass, @NotNull PsiElementFactory factory) {
   PsiClassType superType;
   final PsiManager manager = psiClass.getManager();
   final PsiClass enumClass =
       JavaPsiFacade.getInstance(manager.getProject())
           .findClass("java.lang.Enum", psiClass.getResolveScope());
   if (enumClass == null) {
     try {
       superType = (PsiClassType) factory.createTypeFromText("java.lang.Enum", null);
     } catch (IncorrectOperationException e) {
       superType = null;
     }
   } else {
     final PsiTypeParameter[] typeParameters = enumClass.getTypeParameters();
     PsiSubstitutor substitutor = PsiSubstitutor.EMPTY;
     if (typeParameters.length == 1) {
       substitutor = substitutor.put(typeParameters[0], factory.createType(psiClass));
     }
     superType = new PsiImmediateClassType(enumClass, substitutor);
   }
   return superType;
 }
  public static int insertClassReference(
      PsiClass psiClass, PsiFile file, int startOffset, int endOffset) {
    final Project project = file.getProject();
    PsiDocumentManager documentManager = PsiDocumentManager.getInstance(project);
    documentManager.commitAllDocuments();

    final PsiManager manager = file.getManager();

    final Document document =
        FileDocumentManager.getInstance().getDocument(file.getViewProvider().getVirtualFile());

    final PsiReference reference = file.findReferenceAt(startOffset);
    if (reference != null) {
      final PsiElement resolved = reference.resolve();
      if (resolved instanceof PsiClass) {
        if (((PsiClass) resolved).getQualifiedName() == null
            || manager.areElementsEquivalent(psiClass, resolved)) {
          return endOffset;
        }
      }
    }

    String name = psiClass.getName();
    if (name == null) {
      return endOffset;
    }

    assert document != null;
    document.replaceString(startOffset, endOffset, name);

    int newEndOffset = startOffset + name.length();
    final RangeMarker toDelete = insertTemporary(newEndOffset, document, " ");

    documentManager.commitAllDocuments();

    PsiElement element = file.findElementAt(startOffset);
    if (element instanceof PsiIdentifier) {
      PsiElement parent = element.getParent();
      if (parent instanceof PsiJavaCodeReferenceElement
          && !((PsiJavaCodeReferenceElement) parent).isQualified()
          && !(parent.getParent() instanceof PsiPackageStatement)) {
        PsiJavaCodeReferenceElement ref = (PsiJavaCodeReferenceElement) parent;

        if (psiClass.isValid()
            && !psiClass.getManager().areElementsEquivalent(psiClass, resolveReference(ref))) {
          final boolean staticImport = ref instanceof PsiImportStaticReferenceElement;
          PsiElement newElement;
          try {
            newElement =
                staticImport
                    ? ((PsiImportStaticReferenceElement) ref).bindToTargetClass(psiClass)
                    : ref.bindToElement(psiClass);
          } catch (IncorrectOperationException e) {
            return endOffset; // can happen if fqn contains reserved words, for example
          }

          final RangeMarker rangeMarker = document.createRangeMarker(newElement.getTextRange());
          documentManager.doPostponedOperationsAndUnblockDocument(document);
          documentManager.commitDocument(document);

          newElement =
              CodeInsightUtilCore.findElementInRange(
                  file,
                  rangeMarker.getStartOffset(),
                  rangeMarker.getEndOffset(),
                  PsiJavaCodeReferenceElement.class,
                  JavaLanguage.INSTANCE);
          rangeMarker.dispose();
          if (newElement != null) {
            newEndOffset = newElement.getTextRange().getEndOffset();
            if (!(newElement instanceof PsiReferenceExpression)) {
              PsiReferenceParameterList parameterList =
                  ((PsiJavaCodeReferenceElement) newElement).getParameterList();
              if (parameterList != null) {
                newEndOffset = parameterList.getTextRange().getStartOffset();
              }
            }

            if (!staticImport
                && !psiClass
                    .getManager()
                    .areElementsEquivalent(psiClass, resolveReference((PsiReference) newElement))
                && !PsiUtil.isInnerClass(psiClass)) {
              final String qName = psiClass.getQualifiedName();
              if (qName != null) {
                document.replaceString(
                    newElement.getTextRange().getStartOffset(), newEndOffset, qName);
                newEndOffset = newElement.getTextRange().getStartOffset() + qName.length();
              }
            }
          }
        }
      }
    }

    if (toDelete.isValid()) {
      document.deleteString(toDelete.getStartOffset(), toDelete.getEndOffset());
    }

    return newEndOffset;
  }