@SuppressWarnings("UnusedDeclaration")
  @Nullable
  private Long selectLong(@NotNull Selector selector, @NotNull String source) throws Exception {
    return extractValueAndCheckType(selector, source, Long.class);
  }
@SuppressWarnings("UnusedDeclaration")
  @Nullable
  private Long selectLong(@NotNull Selector selector, @NotNull String source)