public static Set<String> asSet(String... elements) {
    if (elements == null) return new HashSet<>();
    Set<String> set = new HashSet<>(elements.length);
    Collections.addAll(set, elements);
    return set;
  }
Return an interned map with identical contents as the given map.
@param map The map whose strings will be interned
@return An identical map with its strings interned.
standalone-metastore/metastore-common/src/main/java/org/apache/hadoop/hive/metastore/utils/StringUtils.java