Validating domain objects hibernate part 5


In fact, creating a custom validation constraint and a matching custom validator is a no-brainer process that boils down to following these steps: method allows to specify which constraints should be validated when the validator is called, in a per-group basis.By default, all the constraints are checked within the default group, meaning that each constraint will be validated regardless of the target object’s lifecycle phase.Finally, the Finally, validating a user object looks exactly the same as when using the default email validator. Of course, I’m not saying that you’ll always need to mess up your life by creating custom constraints and validators, as this would downgrade the functionality of Java Beans Validation to nearly zero.Nevertheless, from a design point of view it is useful to know that the standard offers a decent level of customization.



As building such web application is definitively out of this post’s scope, the task will be left as homework for you, in case that you want to start pulling the reins of Hibernate Validator in the Web terrain.It’s possible, however, to set up different groups in the form of simple interfaces, and specify which constraints must be validated according to a particular lifecycle phase.For brevity’s sake, the above example uses the default group.Should its state be validated before being persisted or updated in a database, or when passed around to other layer(s)? Prior to Java EE 6, Java didn’t provide a standard way of validating the fields of a domain class by mean of a centralized mechanism. The Java Beans Validation specification makes it fairly easy to selectively validate class fields (and even entire classes) by using constraints declared with a few intuitive annotations.

At the time of this writing, JSR 303 has only two compliant implementations that you can pick up out there, Apache BVal and Hibernate Validator.

It’s possible, however, to get the same result by using a standard instances here and there, and validate the constrained classes in multiple places, even in the wrong ones!



Validating domain objects hibernate part 5 comments


  • Hibernate Validator Reference Guide - Red Hat Customer Portal profil de paulette60

    paulette60

    The Hibernate Validator Reference Guide for JBoss Enterprise Web Platform 5 and its patch releases. Chapter 1. Introduction. Annotations are a very convenient and elegant way to specify invariant constraints for a domain model. You can, for example, express that a property should never be null, that the account.…
  • Hibernate Validator - Documentation profil de paulette60

    paulette60

    Field-level constraints; 2.1.2. Property-level constraints; 2.1.3. Class-level constraints; 2.1.4. Constraint inheritance; 2.1.5. Object graphs. 2.2. Validating constraints. 2.2.1. Obtaining a. This chapter will show you how to get started with Hibernate Validator, the reference implementation RI of Bean Validation. For the.…