The javadoc for @PostConstruct says, "The PostConstruct annotation is used on a method that needs to be executed after dependency injection is done to perform any initialization." It sounds like it's saying that in a properly defined class, all initialization would be completed after a call to a @PostConstruct annotated method, at which point it would be safe to do validation. If a class doesn't adhere to that, then it's out of our hands.

@PostConstruct on @ApplicationScoped bean called too late in case @Valid is annotated on a business method ---------------------------------------------------------------------------------------------------------- Key: WFLY-11956 URL: https://issues.jboss.org/browse/WFLY-11956 Project: WildFly Issue Type: Bug Components: Bean Validation, REST Affects Versions: 16.0.0.Final Reporter: Joerg Baesner Assignee: Ronald Sigal Priority: Major Attachments: logging.txt, playground.zip Having a bean class with {{@ApplicationScoped}}, which has a {{@PostConstruct}} and is implementing the following _Interface_: {code} @Path("/validated") public interface ValidatedJaxRsInterface { @GET @Valid @Produces(MediaType.APPLICATION_JSON) GreetingModel getHelloGreeting(); } {code} will result in calling the {{getHelloGreeting}} method of the implementation class twice *_before_* the {{@PostConstruct}} is getting executed. This can be reproduced with the attached reproducer application...