operator-precedencehibernate-validator

Control validation annotations order?


A field has two validation annotations

@NotEmpty
@Length(min=3,max=100)
String firstName;

Observation

If that field is left empty, then the resulting violations vary in order:

Questions

How does Hibernate specify the order in which validations (annotations) are processed? Can this validation order be customized?

Thanks in advance.


Solution

  • Use JSR-303 validation groups.

    If no groups are specified a constraint is part of the Default Bean Validation group (see: javax.validation.groups.Default).

    Create an interface to be your "Extended" (or whatever you want to call it) group:

    public interface Extended{}
    

    Now create an interface that will have the javax.validation.GroupSequence annotation.

    @GroupSequence({Default.class, Extended.class})
    public interface MySequence {}
    

    Set the validation groups on your constraints

    @NotEmpty // If no group is specified it is part of the default group
    @Length(min=3,max=100, groups = Extended.class)
    String firstName;
    

    Pass MySequence to your validator call.

    validator.validate(object, MySequence.class);
    

    As specified by your @GroupSequence the default constraints will be validated first and if no contraint violations are encountered it will move on to the extended group.