code: @Nonnull
    private static EValidity _validateJson (@Nonnull @WillClose final Reader aReader)
    {
      // Force silent parsing :)
      final ESuccess eSuccess = parseJson (aReader,
                                           new DoNothingJsonParserHandler (),
                                           (IJsonParserCustomizeCallback) null,
                                           ex -> {});
      return EValidity.valueOf (eSuccess.isSuccess ());
    }
docs: Validate a JSON without building the tree in memory.
  
  @param aReader
  The reader to read from. Should be buffered. May not be
  <code>null</code>.
  @return {@link EValidity#VALID} if the JSON is valid,
  {@link EValidity#INVALID} otherwise.