final Optional<String> reference, final String errorAppTag, final String errorMessage) {
this.min = Preconditions.checkNotNull(min, "min must not be null.");
this.max = Preconditions.checkNotNull(max, "max must not be null.");
final Optional<String> reference, final String errorAppTag, final String errorMessage) {
this.min = Preconditions.checkNotNull(min, "min must not be null.");
this.max = Preconditions.checkNotNull(max, "max must not be null.");