Portable Extension Wishlist

Work in progress list of enhancements to javax.enterprise.inject.spi for the CDI 1.0 maintenance release and CDI 1.1.

Producer field initializers

This is a generalization of CDI's built-in support for Java EE component environment resources, allowing portable extensions to define their own annotations that work like @Resource, @PersistenceContext, @EJB and friends in a producer field declaration. For example:

@Produces @JMS(topic=".../prices") 
@Prices Topic topic;

We would need to introduce a new interface in the SPI package:

public interface Initializer<X> {
    public X getInitialValue(AnnotatedField<?> field);
}

Along with a ProcessProducerField event type extending ProcessProducer with a setInitializer() method.

Ability to obtain a container-created bean for a Producer or InjectionTarget or for an AnnotatedType

A convenience feature to minimize the number of anonymous classes implementing Bean and minimize implementation errors.

Add:

• createBean(types, qualifiers, scope, name, stereotypes, alternative, beanClass, InjectionTarget it), and
• createBean(atypes, qualifiers, scope, name, stereotypes, alternative, beanClass, nullable, Producer p)

to BeanManager.

Or, perhaps:

• introduce BeanAttributes interface as a supertype of Bean, with
• BeanManager.createBeanAttributes(), together with
• createBean(BeanAttributes ba, InjectionTarget it) and createBean(BeanAttributes ba, Producer p).

Also add:

• createBean(AnnotatedType at)

to BeanManager.

Ability to override attributes of a Bean

Wrapping the AnnotatedType just to add an annotation is a real PITA.

We should make it possible to mess with the scope/qualifiers/name/etc of a bean either from ProcessBean event, or, better from a ProcessBeanAttributes event which lets you wrap the BeanAttributes or give the container a new one created with BeanManager.createBeanAttributes().

Ability to process modules

Add ProcessModule event which let's you mess with the enabled alternatives/interceptors/decorators and more:

public interface ProcessModule {
    public Set<Class> getAlternatives();
    public List<Class> getInterceptors();
    public List<Class> getDecorators();
    public Set<AnnotatedType> getAnnotatedTypes();
    public Set<Extension> getExtensions();
}

Ability to wrap the InjectionPoint

Add ProcessInjectionPoint event, along with BeanManager.createInjectionPoint(annotatedMember).

Allow injection of Instance<X> into portable extensions

It's more convenient for a portable extension to use Instance than BeanManager.getBeans() followed by BeanManager.getInstance().

Clarify that there can be multiple AnnotatedType instances per Java class

This is not 100% clear in the spec.

Obtain Extension instances from BeanManager

Add public <T extends Extension> T getExtension(Class<T> extensionClass) to BeanManager.

Use Module object, instead of Class for inter-module dependency resolution

We should add Module and Bean.getModule() instead of using getBeanClass() as a proxy for the module when doing inter-module dependency resolution.