public static Set<String> getHtmlMethodSignatures(@NotNull PsiMethod method, @Nullable LanguageLevel preferredFormat) {
    final Set<String> signatures = new LinkedHashSet<>();
    if (preferredFormat != null) signatures.add(formatMethodSignature(method, preferredFormat));
    signatures.add(formatMethodSignature(method, LanguageLevel.JDK_10));
    signatures.add(formatMethodSignature(method, LanguageLevel.JDK_1_8));
    signatures.add(formatMethodSignature(method, LanguageLevel.JDK_1_5));
    return signatures;
  }
public static Set<String> getHtmlMethodSignatures(@NotNull PsiMethod method, @Nullable LanguageLevel preferredFormat)