Application layer agnostic validation
Hibernate Validator allows to express and validate application constraints. The default metadata source are annotations, with the ability to override and extend through the use of XML. It is not tied to a specific application tier or programming model and is available for both server and client application programming. But a simple example says more than 1000 words:
public class Car {
@NotNull
private String manufacturer;
@NotNull
@Size(min = 2, max = 14)
private String licensePlate;
@Min(2)
private int seatCount;
// ...
}Extendable
Hibernate Validator offers a configurable bootstrap API as well as a range of built-in constraints. The latter can easily be extended by creating custom constraints.
Rich metadata API
Hibernate Validator gives access to constraint configuration via a metadata API facilitating, for example, tooling integration.
Reference implementation
Hibernate Validator 6.x is the reference implementation Bean Validation 2.0.
Added value
Hibernate Validator offers additional value on top of the features required by Bean Validation. For example, a programmatic constraint configuration API as well as an annotation processor which plugs into the build process and raises compilation errors whenever constraint annotations are incorrectly used.
