@Nullable
	@Override
	protected Query buildQuery() {
		String search = stringValue.get();
		String id = stringPredicateId.get();

		// Skip for blank input
		if (search.isBlank())
			return null;

		// Validate regex input
		if (id.contains("regex") && !RegexUtil.validate(search).valid())
			return null;

		// Skip if unrecognized string predicate id
		StringPredicate predicate = stringPredicateProvider.newBiStringPredicate(id, search);
		if (predicate == null)
			return null;

		return new StringQuery(predicate);
	}
@return String value property to search with.
recaf-ui/src/main/java/software/coley/recaf/ui/pane/search/StringSearchPane.java