[windup-dev] CDI question - producer

[Pete Muir]

There shouldn’t be any difference, but there is no need to to have @ApplicationScoped on both the producer method and the managed bean you declare it on, and do lazy init. Putting it on the producer method means CDI will cache it. Putting it on the declaring bean means the same bean will be called each time to execute the method. With the code you show, the simplest thing is to just put @Produces @ApplicationScoped on the create() method.

As a side note, you probably want to use @ApplicationScoped not @Singleton.

On 9 Sep 2014, at 08:08, Ondrej Zizka <ozizka at redhat.com> wrote:

> Hi, with this
> 
> ----------------------------------------------------------------
> @Singleton
> public class GraphContextFactoryImpl implements GraphContextFactory
> {
>    @Inject
>    private GraphApiCompositeClassLoaderProvider graphApiCompositeClassLoaderProvider;
> 
>    @Inject
>    private Imported<Service<? extends VertexFrame>> graphServices;
> 
>    @Inject
>    private GraphTypeRegistry graphTypeRegistry;
> 
>    private GraphContext graphContext;
> ----------------------------------------------------------------
> 
> 
> is there a difference between the following two?
> Basically I just moved the core of the creation.
> A is master, B is my branch, results in the GraphContext being created at each @Inject.
> I think I am missing something here.
> 
> Thanks, Ondra
> 
> 
> ---A-------------------------------------------------------------
>   @Override
>    public GraphContext create(){
>        return produceGraphContext();
>    }
> 
>    @Produces  @ApplicationScoped
>    public GraphContext produceGraphContext(){
>         if (this.graphContext == null){
>            this.graphContext = new GraphContextImpl(graphServices, this.graphTypeRegistry, this.graphApiCompositeClassLoaderProvider);
>        }
>        return graphContext;
>    }
> 
> ----B-----------------------------------------------------------
> 
>    @Override
>    public GraphContext create()    {
>        return new GraphContextImpl(
>            this.graphServices,
>            this.graphTypeRegistry,
>            this.graphApiCompositeClassLoaderProvider);
>    }
> 
>    @Produces  @ApplicationScoped
>    public GraphContext produceGraphContext(){
>        if (this.graphContext == null) {
>            this.graphContext = this.create();
>        }
>        return graphContext;
>    }
>