[hibernate-issues] [Hibernate-JIRA] Commented: (HV-46) Constraints should not compare against empty string values

Constraints should not compare against empty string values ---------------------------------------------------------- Key: HV-46 URL: http://opensource.atlassian.com/projects/hibernate/browse/HV-46 Project: Hibernate Validator Issue Type: Improvement Components: validators Affects Versions: 3.0.0.ga Reporter: Hayo Schmidt Constraints should not compare against empty input strings nor null values, except for @NotNull/@NotEmpty annotation. The way many contraints are currently implemented, the validation framework is almost useless for attributes that are allowed to be empty or null. In a web based environment you often have return values of null or empty strings. And you cannot predict, what kind of non-value the browser returns. For example - @Min(value=0) leads to an error, if value is empty string. "" is regarded to be less than zero. - @Digits(integerDigits=4) does not allow an empty input: "Numeric value out of bounds (<4 digits>.<0 digits> expected)" - @Range(min=0), if empty input: "must be between 0 and 9223372036854775807" As there are already the @NotNull and the @NotEmpty annotation, there is absolutely no need for comparing other constraints against empty values (except Length min). Whitespace-only strings should also be taken into account for numerical constraints. The behaviour should be documented in the Reference Guide.