I had a problem because I miswrote my constraint

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy={CancellationCode.StringValidator.class})
public @interface CancellationCode {
	String message() default "org.jboss.jdf.example.ticketmonster.model.CancellationCode.message";
	Class<?>[] groups() default {};
	Class<? extends Payload>[] payload() default {};
}

Note the missing {} around the message default key.

We might want to detect that in the annotation processor by checking the following pattern:

• long ish without space
• dots
• no {} around