[seam-dev] CDI with generic class and the hell of type erasure.

[José Rodolfo Freitas]

Hey guys, how you doing?

I'm trying to achieve something that might be impossible, but before
concluding that, I'd like to ask you, CDI gurus!

I have the following class:

public class Foo<T> {

    public TypedQuery<T> getQuery(){

    }

}

As you can Imagine, inside my getQuery method, I'd have to use "T.class" to
make it TypedQuery. which is impossible due java generics type erasure.

so I'd have to build a private field to hold the t.class for me.

public class Foo<T> {

    private Class<T> klass;

    public TypedQuery<T> getQuery(){

    }

    public void setKlass(Class<T> klass){
        this.klass = klass;
    }
}

The problem is that forcing this 'setKlass' feels very ugly to the api, and
it's not very error prone, since one could easily forget to set this
configuration.

So I had an Idea: force the setKlass inside the constructor:

public class Foo<T> {

    private Class<T> klass;

    public Foo(Class<T> klass){
        this.klass = klass;
    }

    public TypedQuery<T> getQuery(){

    }

}

Unfortunatelly, this breaks cdi, since it cannot inject it anymore. At
least AFAIK.

So, is there a way out of this? maybe using a secret solder feature?
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