private void addNewClause(
      Collection<String> elements,
      Collection<String> additional,
      Project project,
      boolean isExtends)
      throws IncorrectOperationException {
    if (elements.isEmpty() && additional.isEmpty()) return;

    StringBuilder classText = new StringBuilder();
    classText.append("class A ");
    classText.append(isExtends ? "extends " : "implements ");

    for (String str : elements) {
      classText.append(str);
      classText.append(", ");
    }

    for (String str : additional) {
      classText.append(str);
      classText.append(", ");
    }

    classText.delete(classText.length() - 2, classText.length());

    classText.append(" {}");

    final GrTypeDefinition definition =
        GroovyPsiElementFactory.getInstance(project).createTypeDefinition(classText.toString());
    GroovyPsiElement clause =
        isExtends ? definition.getExtendsClause() : definition.getImplementsClause();
    assert clause != null;

    PsiElement addedClause = myClass.addBefore(clause, myClass.getBody());
    JavaCodeStyleManager.getInstance(project).shortenClassReferences(addedClause);
  }
  public static boolean processDeclarations(
      @NotNull GrTypeDefinition grType,
      @NotNull PsiScopeProcessor processor,
      @NotNull ResolveState state,
      @Nullable PsiElement lastParent,
      @NotNull PsiElement place) {
    if (place instanceof GrCodeReferenceElement && lastParent instanceof GrModifierList) {
      final PsiElement possibleAnnotation =
          PsiTreeUtil.skipParentsOfType(place, GrCodeReferenceElement.class);
      if (possibleAnnotation instanceof GrAnnotation
          && possibleAnnotation.getParent() == lastParent) {
        return true; // don't process class members while resolving annotation which annotates
                     // current class
      }
    }

    for (final PsiTypeParameter typeParameter : grType.getTypeParameters()) {
      if (!processElement(processor, typeParameter, state)) return false;
    }

    NameHint nameHint = processor.getHint(NameHint.KEY);
    String name = nameHint == null ? null : nameHint.getName(state);
    ClassHint classHint = processor.getHint(ClassHint.KEY);
    final PsiSubstitutor substitutor = state.get(PsiSubstitutor.KEY);
    final PsiElementFactory factory = JavaPsiFacade.getElementFactory(place.getProject());

    boolean processInstanceMethods =
        (shouldProcessMethods(classHint) || shouldProcessProperties(classHint))
            && shouldProcessInstanceMembers(grType, lastParent);

    LanguageLevel level = PsiUtil.getLanguageLevel(place);
    if (shouldProcessProperties(classHint)) {
      Map<String, CandidateInfo> fieldsMap = CollectClassMembersUtil.getAllFields(grType);
      if (name != null) {
        CandidateInfo fieldInfo = fieldsMap.get(name);
        if (fieldInfo != null) {
          if (!processField(
              grType,
              processor,
              state,
              place,
              processInstanceMethods,
              substitutor,
              factory,
              level,
              fieldInfo)) {
            return false;
          }
        } else if (grType.isTrait() && lastParent != null) {
          PsiField field = findFieldByName(grType, name, false, true);
          if (field != null && field.hasModifierProperty(PsiModifier.PUBLIC)) {
            if (!processField(
                grType,
                processor,
                state,
                place,
                processInstanceMethods,
                substitutor,
                factory,
                level,
                new CandidateInfo(field, PsiSubstitutor.EMPTY))) {
              return false;
            }
          }
        }
      } else {
        for (CandidateInfo info : fieldsMap.values()) {
          if (!processField(
              grType,
              processor,
              state,
              place,
              processInstanceMethods,
              substitutor,
              factory,
              level,
              info)) {
            return false;
          }
        }
        if (grType.isTrait() && lastParent != null) {
          for (PsiField field : CollectClassMembersUtil.getFields(grType, true)) {
            if (field.hasModifierProperty(PsiModifier.PUBLIC)) {
              if (!processField(
                  grType,
                  processor,
                  state,
                  place,
                  processInstanceMethods,
                  substitutor,
                  factory,
                  level,
                  new CandidateInfo(field, PsiSubstitutor.EMPTY))) {
                return false;
              }
            }
          }
        }
      }
    }

    if (shouldProcessMethods(classHint)) {
      Map<String, List<CandidateInfo>> methodsMap =
          CollectClassMembersUtil.getAllMethods(grType, true);
      boolean isPlaceGroovy = place.getLanguage() == GroovyFileType.GROOVY_LANGUAGE;
      if (name == null) {
        for (List<CandidateInfo> list : methodsMap.values()) {
          for (CandidateInfo info : list) {
            if (!processMethod(
                grType,
                processor,
                state,
                place,
                processInstanceMethods,
                substitutor,
                factory,
                level,
                isPlaceGroovy,
                info)) {
              return false;
            }
          }
        }
      } else {
        List<CandidateInfo> byName = methodsMap.get(name);
        if (byName != null) {
          for (CandidateInfo info : byName) {
            if (!processMethod(
                grType,
                processor,
                state,
                place,
                processInstanceMethods,
                substitutor,
                factory,
                level,
                isPlaceGroovy,
                info)) {
              return false;
            }
          }
        }
      }
    }

    final GrTypeDefinitionBody body = grType.getBody();
    if (body != null) {
      if (shouldProcessClasses(classHint)) {
        for (PsiClass innerClass : getInnerClassesForResolve(grType, lastParent, place)) {
          final String innerClassName = innerClass.getName();
          if (nameHint != null && !innerClassName.equals(nameHint.getName(state))) {
            continue;
          }

          if (!processor.execute(innerClass, state)) {
            return false;
          }
        }
      }
    }

    return true;
  }