Exending EntityQuery

[monkeyden]

I have 4 different persistence contexts in my application, and I'm extending EntityQuery for each of them so I can override getPersistenceContextName().  I was getting an IllegalStateException from this method:

@Create
   public void validate()
   {
      if ( getEjbql()==null )
      {
         throw new IllegalStateException("ejbql is null");
      }
   }

1. I wasn't aware that Seam invoked @Create methods recursively.


2. This bit of code forces me to override getEjbql() because it doesn't give me a chance to call setEjbql().

Is it necessary to have this restriction on @Create?  Why not call validate on getResultList(), getSingleResult(), etc.?

Thanks

[monkeyden]

Also, can someone tell me why the @Factory method isn't being executed in this class?  The functional goal is to, at app startup, outject a static list (suffixes) to application context.  It appears that Seam is ignoring the annotations in this class.  Note that StaticQueryController is a subclass of EntityQuery and only overrides getPersistenceContextName().  I suspect something in the EntityQuery or Query is interfering.

I get this error:

Caused by: org.jboss.seam.RequiredException: @Out attribute requires non-null value: suffixList.suffixes

@Startup
@Name("suffixList")
@Scope(ScopeType.APPLICATION)
public class SuffixList extends StaticQueryController<Suffix> {

    private static final String EJBQL = "SELECT s FROM Suffix s";

    @Out(scope=ScopeType.APPLICATION)
    private List<Suffix> suffixes;

    @Factory("suffixes")
    public void load() {
        suffixes = Collections.unmodifiableList(getResultList());
        log.debug("Found #0 suffixes", suffixes.size());
    }

    @Override
    public String getEjbql(){
        return SuffixList.EJBQL;
    }

    public SuffixList() {
        setEjbql(EJBQL);
        setOrder("id");
    }
}

Thanks

[swd847]

Not sure about the first question.
With the second question you are mixing @Out and @Factory. I think what you really want is @Unwrap. As it is the load() method will only be called if someone requests the value of suffixes either via EL or @In(create=true). Try this:

@Startup
@Name("suffixes")
@Scope(ScopeType.APPLICATION)
public class SuffixList extends StaticQueryController<Suffix> {

    private static final String EJBQL = "SELECT s FROM Suffix s";


    @Unwrap
    public List<Suffix> load() {
        return Collections.unmodifiableList(getResultList());
        //log.debug("Found #0 suffixes", suffixes.size());
    }

    @Override
    public String getEjbql(){
        return SuffixList.EJBQL;
    }

    public SuffixList() {
        setEjbql(EJBQL);
        setOrder("id");
    }
}

[monkeyden]

I think what you really want is @Unwrap.

Hi Stuart,
Thanks for the response.  That's how I originally expected @Unwrap would behave.  There is one problem with that, however.  What actually happens is the wrapper class is outjected to the specified scope, not the result of the @Unwrap method.  Use of the @Unwrap annotation implies that you are not interested in the wrapper class.  I would find my expected behavior of @Unwrap to be very useful.  Maybe it's a bug, maybe it's a feature request.

[swd847]

The simple way is to put an @Create method on you bean and manually stuff it into the application context (I think it is something like Contexts.getApplicationContext.set()). You could also create another application scoped @Startup component that tries to inject suffixes with create=true. Either way don't worry about the @Out annotation.

[monkeyden]

I tried the former, but the issue I mentioned in the original post precludes this.  The Query class (parent of EntityQuery) steals the @Create annotation, simply to validate the ejbql property.  Seam does not allow multiple @Create methods in the hierarchy. 

I was already considering the latter suggestion and ended up going with it.  However, the expected behavior I mentioned above would have been much more slick.  Thanks for spending the time.