DI with CDI and 3rd party class: avoid constructor doing business logic called multiple times for each proxy construction

Question

I'm relativly new to EE / CDI for DI so maybe one of you could provide me with some tips for my problem:

I've got a 3rd party class which I would like to inject into other beans. In spring just needs some <bean> declaration and it's done. Using cdi it now takes a factory class:

public class XProducer {    
    @Produces
    @ApplicationScoped
    public X createX(){
        return new X();
    }
}

Unfortunatly X`s constructor invokes rather expensive business logic and every time a proxy is created by cdi it's called but I can't change X's behaviour. This leaves me with the following options I don't really like:

wrapping X in some ugly Holder-class,
creating some facade and have to delgate methods to X

Are there any other options left?

John Ament · Accepted Answer · 2016-04-21T12:44:37.253

2

This is probably a case where you want to use @javax.inject.Singleton since its a third party, you won't need interceptor support, and singleton does not generate a proxy, so the constructor will only be called once.

edited Apr 21 '16 at 12:44

answered Apr 21 '16 at 11:39

John Ament

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Okay, using EJB then :) I initially rejected `@Singleton` due to container managed concurrency creating a bottleneck having overlooked it can be disabled with `@ConcurrencyManagement(BEAN)`. – J. Doe Apr 22 '16 at 10:31
Why EJB? If you using `@javax.inject.Singleton` its from JSR-330, not EJB. – John Ament Apr 22 '16 at 20:39

DI with CDI and 3rd party class: avoid constructor doing business logic called multiple times for each proxy construction

1 Answers1