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javajakarta-eeejbcdi

What's the default scope for a bean created by a @Produces method without a scope annotation?


I've got a method with a @Produces annotation that creates an Apple.

When I use it with @ApplicationScoped like this

public class AppleProducer {
    @ApplicationScoped
    @Produces
    public Apple createApple() {
        return new Apple();
    }
}

then the Apple gets created only once for the whole application.

When I use it with @RequestScoped like this

public class AppleProducer {
    @RequestScoped
    @Produces
    public Apple createApple() {
        return new Apple();
    }
}

then it gets created for every request.

But what if I do not specify a scope?

public class AppleProducer {
    @Produces
    public Apple createApple() {
        return new Apple();
    }
}

How often will the Apple be created? I suspect on every access, is it correct? Is there documentation about this?


Solution

  • It's @Dependent.

    According to "2.4.4. Default scope" from the CDI (1.2) specification:

    When no scope is explicitly declared by annotating the bean class or producer method or field the scope of a bean is defaulted.

    The default scope for a bean which does not explicitly declare a scope depends upon its declared stereotypes:

    • If the bean does not declare any stereotype with a declared default scope, the default scope for the bean is @Dependent.

    • If all stereotypes declared by the bean that have some declared default scope have the same default scope, then that scope is the default scope for the bean.

    • If there are two different stereotypes declared by the bean that declare different default scopes, then there is no default scope and the bean must explicitly declare a scope. If it does not explicitly declare a scope, the container automatically detects the problem and treats it as a definition error.

    If a bean explicitly declares a scope, any default scopes declared by stereotypes are ignored.