Method empty

core/src/main/java/org/apache/calcite/util/Holder.java:65–68

Creates a holder containing null.

()

  /** Creates a holder containing null. */
  @SuppressWarnings("ConstantConditions")
  public static <E> Holder<@Nullable E> empty() {
    return new Holder<@Nullable E>(null);
  }
}