Calling EL with parameter is sometimes null

[serkan.s.eskici.online.nl]

Hi.

I've a weird problem with calling EL with parameters from my xhtml page.

The situation is as follows:

1. I have a master page in which a complex html table gets rendered by making use of 3 nested c:foreach loops.


2. In one of the loops I render a link which calls an action and then redirects to the detail page. I pass an object as a parameter in the action.


3. In the detail page I load an entity with its details and with a logo (lob).


4. The whole stuff is inside a LRC (long running conversation).

Well, the point is that everything works fine, until I add/upload a logo to the entity. After I do that, the detail page is shown and the current conversation gets destroyed (automatically). And when I go back to the master page and click the link again, I get a NPE because the parameter in the EL also gets null (I think because the LRC gets ended).

But this doesn't happen when I don't add a logo the Entity Bean (see below).

So here's my code:

@Entity   
public class Contact implements Serializable {
    @Id
    @GeneratedValue
    @Column(nullable = false)
    private Long id;

    @Lob
    @Column()
    private byte[] logo;
}

@Name("itemBean")
@Scope(CONVERSATION)
public class ItemBean {
   
   @In
   private ItemService service;
  
   @Out
   private List<ItemVO> items;

   @Begin(join=true)
   @Observer("some.event.happened")
   public void init(){
        this.items = this.service.getItems();
   }
}

@Name("contactBean")
@Scope(CONVERSATION)
public class ContactBean {

   @In 
   private ContactService contactService;
  
   @Out
   private Contact selectedContact;

   
   public void getContact(DetailVO detail){
        this.selectedContact = this.contactService.getContact(detail.name, detail.address);
   }
}

master.xhtml:

<h:form>
  <c:forEach items="#{items}" var="item>
    <h:panelGrid columns="4" rowClasses="odd,even" columnClasses=",right-aligned, ,last right-aligned">
        <f:facet name="header">
         <h:panelGroup> ... </h:panelGroup>
        </f:facet>
        <c:forEach items="#{item.types}" var="type">
         <c:forEach items="#{type.details}" var="detail" varStatus="status">
               <h:commandLink action="#{contactBean.getContact(detail)}" value="#{detail.name}" />   ----> this redirects to detail.xhtml
               <h:commandLink action="#{contactBean.getContact(detail)}" value="#{detail.name}">  ----> I also tried this one.
                    <s:conversationId/>
                    <s:concersationPropagation type='join' />
               </h:commandLink>
            </c:forEach>
        </c:forEach>
    </h:panelGrid>
  </c:forEach>
<h:/form>


detail.xhtml:
...
<h:inputText value="#{selectedContact.name}" />
<s:graphicImage value="#{selectedContact.logo}" alt="logo" rendered="#{not empty selectedContact.logo}">
   <s:transformImageSize height="80" maintainRatio="true" />
</s:graphicImage>
... and so on

I use Seam 2.1.2 with JBoss AS 4.2.3.

Any help is welcome.

Cheers,
Serkan

[serkan.s.eskici.online.nl]

Sorry, I need to clarify one point:

The detail that gets selected on the master page, must also be outjected and re-used in the detail page. That's something I did wrong in the code above.

Thus the ContactBean should be as follows:

@Name("contactBean")
@Scope(CONVERSATION)
public class ContactBean {

   @In 
   private ContactService contactService;
  
   @Out
   private DetailVO selectedDetail;

   @Out
   private Contact contact;

   
   public void getContact(DetailVO detail){
        this.selectedDetail = detail;
        this.contact = this.contactService.getContact(detail.name, detail.address);
   }
}

So the problem is that selectedDetail is null in the EL and the conversation gets ended. And all of this happens after I add a lob to the Entity Bean.