ApplicationInterrogator.java

// Here's a neat way to ask an Application for its classes and singletons
// before the CDI container is up.  That should let you register only those
// beans that should be registered.

private static final <T extends Application> void registerClassesAndSingletons(final AfterBeanDiscovery event,
                                                                                 final Bean<T> bean,
                                                                                 final BeanManager beanManager)
  {
    Objects.requireNonNull(event);
    Objects.requireNonNull(bean);
    Objects.requireNonNull(beanManager);

    // The contexts aren't active yet, so we can't use Context's get()
    // methods.  Instead, we're going to ask the Bean to create an
    // instance of the Application (this also handles injection
    // partially; i.e. non-synthetic beans are available to be
    // injected but synthetic beans are not).  We'll ask the new
    // Application instance, which is effectively unmanaged, for its
    // classes and singletons.  We'll register all those under the
    // same qualifiers that they might have already plus the ones
    // present on their governing Application.  Then we destroy this
    // unmanaged Application instance.
    
    final CreationalContext<T> cc = beanManager.createCreationalContext(bean);
    final T application = bean.create(cc);
    if (application != null) {
      final Set<Class<?>> classes = application.getClasses();
      if (classes != null && !classes.isEmpty()) {
        for (final Class<?> cls : classes) {
          if (cls != null) {
            event.addBean()
              .scope(Dependent.class)
              .read(beanManager.createAnnotatedType(cls))
              .addQualifiers(bean.getQualifiers());
          }
        }
      }
      final Set<?> singletons = application.getSingletons();
      if (singletons != null && !singletons.isEmpty()) {
        for (final Object singleton : singletons) {
          if (singleton != null) {
            event.addBean()
              .scope(Singleton.class)
              .read(beanManager.createBeanAttributes(beanManager.createAnnotatedType(singleton.getClass())))
              .qualifiers(bean.getQualifiers())
              .createWith(ignored -> singleton);
          }
        }
      }
    }
    bean.destroy(application, cc);
    cc.release();
  }