The Java EE 7 Tutorial
22.3 Grouping Constraints
Constraints may be added to one or more groups. Constraint groups are used to create subsets of constraints so that only certain constraints will be validated for a particular object. By default, all constraints are included in the Default
constraint group.
Constraint groups are represented by interfaces.
public interface Employee {} public interface Contractor {}
Constraint groups can inherit from other groups.
public interface Manager extends Employee {}
When a constraint is added to an element, the constraint declares the groups to which that constraint belongs by specifying the class name of the group interface name in the groups
element of the constraint.
@NotNull(groups=Employee.class) Phone workPhone;
Multiple groups can be declared by surrounding the groups with braces ({
and }
) and separating the groups' class names with commas.
@NotNull(groups={ Employee.class, Contractor.class }) Phone workPhone;
If a group inherits from another group, validating that group results in validating all constraints declared as part of the supergroup. For example, validating the Manager
group results in the workPhone
field being validated, because Employee
is a superinterface of Manager
.
22.3.1 Customizing Group Validation Order
By default, constraint groups are validated in no particular order. There are cases in which some groups should be validated before others. For example, in a particular class, basic data should be validated before more advanced data.
To set the validation order for a group, add a javax.validation.GroupSequence
annotation to the interface definition, listing the order in which the validation should occur.
@GroupSequence({Default.class, ExpensiveValidationGroup.class}) public interface FullValidationGroup {}
When validating FullValidationGroup
, first the Default
group is validated. If all the data passes validation, then the ExpensiveValidationGroup
group is validated. If a constraint is part of both the Default
and the ExpensiveValidationGroup
groups, the constraint is validated as part of the Default
group and will not be validated on the subsequent ExpensiveValidationGroup
pass.