public Collection<PsiElement> getAdditionalElementsToDelete(
      @NotNull final PsiElement element,
      @NotNull final Collection<PsiElement> allElementsToDelete,
      final boolean askUser) {
    if (element instanceof PsiField) {
      PsiField field = (PsiField) element;
      final Project project = element.getProject();
      String propertyName =
          JavaCodeStyleManager.getInstance(project)
              .variableNameToPropertyName(field.getName(), VariableKind.FIELD);

      PsiClass aClass = field.getContainingClass();
      if (aClass != null) {
        boolean isStatic = field.hasModifierProperty(PsiModifier.STATIC);
        PsiMethod[] getters =
            GetterSetterPrototypeProvider.findGetters(aClass, propertyName, isStatic);
        if (getters != null) {
          final List<PsiMethod> validGetters = new ArrayList<>(1);
          for (PsiMethod getter : getters) {
            if (!allElementsToDelete.contains(getter) && (getter != null && getter.isPhysical())) {
              validGetters.add(getter);
            }
          }
          getters =
              validGetters.isEmpty()
                  ? null
                  : validGetters.toArray(new PsiMethod[validGetters.size()]);
        }

        PsiMethod setter = PropertyUtil.findPropertySetter(aClass, propertyName, isStatic, false);
        if (allElementsToDelete.contains(setter) || setter != null && !setter.isPhysical())
          setter = null;
        if (askUser && (getters != null || setter != null)) {
          final String message =
              RefactoringMessageUtil.getGetterSetterMessage(
                  field.getName(),
                  RefactoringBundle.message("delete.title"),
                  getters != null ? getters[0] : null,
                  setter);
          if (!ApplicationManager.getApplication().isUnitTestMode()
              && Messages.showYesNoDialog(
                      project,
                      message,
                      RefactoringBundle.message("safe.delete.title"),
                      Messages.getQuestionIcon())
                  != Messages.YES) {
            getters = null;
            setter = null;
          }
        }
        List<PsiElement> elements = new ArrayList<>();
        if (setter != null) elements.add(setter);
        if (getters != null) Collections.addAll(elements, getters);
        return elements;
      }
    }
    return null;
  }
  public Collection<String> findConflicts(
      @NotNull final PsiElement element, @NotNull final PsiElement[] allElementsToDelete) {
    if (element instanceof PsiMethod) {
      final PsiClass containingClass = ((PsiMethod) element).getContainingClass();

      if (containingClass != null && !containingClass.hasModifierProperty(PsiModifier.ABSTRACT)) {
        final PsiMethod[] superMethods = ((PsiMethod) element).findSuperMethods();
        for (PsiMethod superMethod : superMethods) {
          if (isInside(superMethod, allElementsToDelete)) continue;
          if (superMethod.hasModifierProperty(PsiModifier.ABSTRACT)) {
            String message =
                RefactoringBundle.message(
                    "0.implements.1",
                    RefactoringUIUtil.getDescription(element, true),
                    RefactoringUIUtil.getDescription(superMethod, true));
            return Collections.singletonList(message);
          }
        }
      }
    } else if (element instanceof PsiParameter) {
      final PsiElement scope = ((PsiParameter) element).getDeclarationScope();
      if (scope instanceof PsiMethod) {
        final PsiMethod method = (PsiMethod) scope;
        final PsiClass containingClass = method.getContainingClass();
        if (containingClass != null) {
          final int parameterIndex =
              method.getParameterList().getParameterIndex((PsiParameter) element);
          final PsiMethod methodCopy = (PsiMethod) method.copy();
          methodCopy.getParameterList().getParameters()[parameterIndex].delete();
          final MultiMap<PsiElement, String> conflicts = new MultiMap<>();
          ConflictsUtil.checkMethodConflicts(containingClass, method, methodCopy, conflicts);
          return (Collection<String>) conflicts.values();
        }
      }
    }
    return null;
  }
  @Nullable
  @Override
  public Collection<? extends PsiElement> getElementsToSearch(
      @NotNull PsiElement element,
      @Nullable Module module,
      @NotNull Collection<PsiElement> allElementsToDelete) {
    Project project = element.getProject();
    if (element instanceof PsiPackage && module != null) {
      final PsiDirectory[] directories =
          ((PsiPackage) element).getDirectories(module.getModuleScope());
      if (directories.length == 0) return null;
      return Arrays.asList(directories);
    } else if (element instanceof PsiMethod) {
      final PsiMethod[] methods =
          SuperMethodWarningUtil.checkSuperMethods(
              (PsiMethod) element,
              RefactoringBundle.message("to.delete.with.usage.search"),
              allElementsToDelete);
      if (methods.length == 0) return null;
      final ArrayList<PsiMethod> psiMethods = new ArrayList<>(Arrays.asList(methods));
      psiMethods.add((PsiMethod) element);
      return psiMethods;
    } else if (element instanceof PsiParameter
        && ((PsiParameter) element).getDeclarationScope() instanceof PsiMethod) {
      PsiMethod method = (PsiMethod) ((PsiParameter) element).getDeclarationScope();
      final Set<PsiParameter> parametersToDelete = new HashSet<>();
      parametersToDelete.add((PsiParameter) element);
      final int parameterIndex =
          method.getParameterList().getParameterIndex((PsiParameter) element);
      final List<PsiMethod> superMethods =
          new ArrayList<>(Arrays.asList(method.findDeepestSuperMethods()));
      if (superMethods.isEmpty()) {
        superMethods.add(method);
      }
      for (PsiMethod superMethod : superMethods) {
        parametersToDelete.add(superMethod.getParameterList().getParameters()[parameterIndex]);
        OverridingMethodsSearch.search(superMethod)
            .forEach(
                overrider -> {
                  parametersToDelete.add(
                      overrider.getParameterList().getParameters()[parameterIndex]);
                  return true;
                });
      }

      if (parametersToDelete.size() > 1 && !ApplicationManager.getApplication().isUnitTestMode()) {
        String message =
            RefactoringBundle.message(
                "0.is.a.part.of.method.hierarchy.do.you.want.to.delete.multiple.parameters",
                UsageViewUtil.getLongName(method));
        int result =
            Messages.showYesNoCancelDialog(
                project, message, SafeDeleteHandler.REFACTORING_NAME, Messages.getQuestionIcon());
        if (result == Messages.CANCEL) return null;
        if (result == Messages.NO) return Collections.singletonList(element);
      }
      return parametersToDelete;
    } else if (element instanceof PsiTypeParameter) {
      final PsiTypeParameterListOwner owner = ((PsiTypeParameter) element).getOwner();
      if (owner instanceof PsiMethod && !owner.hasModifierProperty(PsiModifier.STATIC)) {
        final PsiTypeParameterList typeParameterList = owner.getTypeParameterList();
        if (typeParameterList != null) {
          final int index = typeParameterList.getTypeParameterIndex((PsiTypeParameter) element);
          if (index >= 0) {
            final ArrayList<PsiTypeParameter> overriders = new ArrayList<>();
            overriders.add((PsiTypeParameter) element);
            OverridingMethodsSearch.search((PsiMethod) owner)
                .forEach(
                    overrider -> {
                      final PsiTypeParameter[] typeParameters = overrider.getTypeParameters();
                      if (index < typeParameters.length) {
                        overriders.add(typeParameters[index]);
                      }
                      return true;
                    });
            if (overriders.size() > 1) {
              String message =
                  RefactoringBundle.message(
                      "0.is.a.part.of.method.hierarchy.do.you.want.to.delete.multiple.type.parameters",
                      UsageViewUtil.getLongName(owner));
              int result =
                  ApplicationManager.getApplication().isUnitTestMode()
                      ? Messages.YES
                      : Messages.showYesNoCancelDialog(
                          project,
                          message,
                          SafeDeleteHandler.REFACTORING_NAME,
                          Messages.getQuestionIcon());
              if (result == Messages.CANCEL) return null;
              if (result == Messages.YES) return overriders;
            }
          }
        }
      }
    }

    return Collections.singletonList(element);
  }