The @In attribute requires non-null value fix?

[samuraicoder]

Please excuse me I am very new. But in preparing for load-testing we got the following error:

Caused by: javax.el.ELException: /store/shop/layout/template.xhtml @62,52 value="#{coreMetrics.buildCoreMetricsString()}": org.jboss.seam.RequiredException: @In attribute requires non-null value: coreMetrics.customerSession

This next part of the error message tells me what page it occurs on:

2010-05-12 15:05:06,292 ERROR [facelets.viewhandler] Error Rendering View[/store/shop/checkout1.xhtml]

javax.faces.FacesException: javax.el.ELException: /store/shop/layout/template.xhtml @62,52 value="#{coreMetrics.buildCoreMetricsString()}": org.jboss.seam.RequiredException: @In attribute requires non-null value: coreMetrics.customerSession

Is the best fix for this to make sure the customerSession bean is active by setting @In (create equal true)?

        @In(create=true) 
        private ICustomerSession customerSession;

[lvdberg]

Hi Dan,

depends a bit on what you want to do. If you need the component you could use the create is true attribute on the @In annotation or make the component autocreate with the @AutoCreate annotation. If you dont, set the required flag of @In to false.

However, the SIA book makes a clear statement about the required flag. If you have a lot of them in you code, you should try to split up your component in smaller ones.

Leo

[samuraicoder]

Thanks Leo.

I guess I will go with create equals true attribute for now and see how we do.

[asookazian]

It's better to use @AutoCreate on the component being injected rather than create=true (less typing)...

[samuraicoder]

Can you explain why this is better?

Did you mean literally less characters to type? Or do you mean less type-casting or something that you could may help me by explaining.

Thanks a bunch!

[asookazian]

@Name("foo")
@AutoCreate
public class Foo {
  //do something
}

@Name("bar")
public class Bar {
   @In Foo foo;
}

So note above there is no @In(create=true), thus less typing every time you inject that component...

[kem]

Thanks Arbi,

lets imagine Foo has not null properties populated from UI. Because of @AutoCreate, all these properties will be null once Foo is injected in Bar.

I have a similar problem as Dan. I have a Foo object with properties values from UI. I want to pass Foo to Bar in order to use these values inside Bar. @In Foo foo raise the @In attribute requires non-null exception.
@AutoCreate fix this exception issue. However the inject foo has all properties set to null.

Any suggestion how to inject foo with all its properties preserved. Thanks.

Khalil