@NotNull
  private static Collection<PsiField> getWitherFields(@NotNull PsiClass psiClass) {
    Collection<PsiField> witherFields = new ArrayList<>();

    for (PsiField psiField : psiClass.getFields()) {
      if (shouldGenerateWither(psiField)) {
        witherFields.add(psiField);
      }
    }
    return witherFields;
  }
@NotNull
  private static Collection<PsiField> getWitherFields(@NotNull PsiClass psiClass)