@JsonCreator
	public static StringLinkRelation of(String relation) {

		Assert.hasText(relation, "Relation must not be null or empty!");

		return CACHE.computeIfAbsent(relation, StringLinkRelation::new);
	}
@ JsonCreator public static StringLinkRelation of ( String relation ) { Assert . hasText ( relation , "Relation must not be null or empty!" ) ; return CACHE . computeIfAbsent ( relation , StringLinkRelation :: new ) ; }
Returns a (potentially cached) {@link LinkRelation} for the given value.

@param relation must not be {@literal null} or empty.
@return