Can @DataModel be replaced with EntityQuery?

[wilczarz.wilczarz.gmail.com]

DataTable has no problem displaying elements of collection annotated with @DataModel. Populating the same table with entityQuery.dataTable isn't that simple. The scope of entityQuery component seems to be cruicial, but the best I could get was displaying the table properly with scope PAGE. It was useless to me since I wanted to inject the selection to SFSB in the next request. With more desirable scopes, like CONVERSATION the table rendered just empty..

[admin.admin.email.tld]

that's interesting.  can u post some code?

I've never heard of not being able to use conversation scope for a Seam component...

[wilczarz.wilczarz.gmail.com]

Sure. This is my component:

@Name( "clientList" )
@Scope( CONVERSATION )
public class ClientList extends EntityQuery<Client> {
     @Override
     public String getEjbql() {
          return "from Client";
     }     
}

the page that uses it (rendered outside any conversation):

<rich:dataTable id="clientList" var="loopClient" value="#{clientList.dataModel}" >
  <rich:column>
    <h:form>
      <h:commandLink value="#{loopClient.name}" action="#{sampleAction.showClient}" />
    </h:form>     
  </rich:column>
</rich:dataTable>

and my session bean:

@Stateful
@Name( "sampleAction" )
@Scope( CONVERSATION )
public class SampleAction implements SampleLocal {
...
@In(create = true) 
@Out 
@DataModelSelection 
private Client client;
...
@Begin public String showClient() {
...
}

Like I said, for CONVERSATION scope in EntityQuery the table renders empty. Now, everyting works fine with

@DataModel
private List<Client> clients;

@Factory( "clients" )
public void findUsers() {
     clients = entityManager.createQuery("from Client").getResultList();
}

and

<rich:dataTable id="clientList" var="loopClient" value="#{clients}" >
  <rich:column>
    <h:form>
      <h:commandLink value="#{loopClient.name}" action="#{sampleAction.showClient}" />
    </h:form>     
  </rich:column>
</rich:dataTable>

because If no scope is explicitly specified for @DataModel, the scope of the component with the @DataModel attribute is used. That works for the SessionBean, but not for EntityQuery.

[baz]

the page that uses it (rendered outside any conversation):

<rich:dataTable id="clientList" var="loopClient" value="#{clientList.dataModel}" >

try to use resultList instead of datamodel. Here is a link to the seam issue tracker.
JBSEAM-2684

BTW: Can anybody explain why i should use dataModel? I have ever used resultList

[wilczarz.wilczarz.gmail.com]

I've tried that but resultList seems incompatible with @DataModelSelection. Nothing gets injected.

[wilczarz.wilczarz.gmail.com]

Ok, I found a workaround for this problem. The DataModel needs to be created manually in EntityQuery:

@Name( "clientList" )
@Scope( CONVERSATION )
public class ClientList extends EntityQuery<Client> {
     
     @Factory( value = "clients", scope = ScopeType.CONVERSATION )
     public ListDataModel findClients() {
          List<Client> clients = getResultList();
          return new ListDataModel( clients );
     }

     @Override
     public String getEjbql() {
          return "from Client";
     }
}

Generally I think it's a good idea to separate any entity's DataModel population from the SessionBean the selection goes to. I'm just not sure if this is the best way to do it.

[pmuir]

Most likely the ManagedEntityIdentityInterceptor rearing its ugly head - this is turned off by default in trunk, and we are working on a replacement solution for clustering failover.