Jboss 6.3: Stateful bean: cannot get the container to hold conversational state

Question

Scenario: The user clicks "generate list", the system displays the list. Then, the user enters in an email address and clicks on "send list".

There are two client server requests, so to avoid reading the database twice i set up a EJB3 stateful bean. The problem is that i cannot get the bean to hold conversational state across multiple client server requests.

Code: Local interface

@Local
public interface IList{

    public void setList(Collection<String> list);

    public Collection<String> getList();

    public void remove();


}

Code: Bean

@Stateful
public class List implements IList{

    private Collection<String> list;

    @Override
    public void setList(Collection<String> list) {

        this.list= list;

    }

    @Override
    public Collection<String> getList() {

        return this.list;

    }

    @Remove
    @Override
    public void remove(){

    }
}

code: ejb-jar.xml: only the data encapsulated by the session tags for simplicity

<session>
    <ejb-name>List</ejb-name>
    <ejb-class>com.lists.List</ejb-class>
</session>

This is how i look up the bean and set the list

InitialContext ic = new InitialContext();
IList irc = (IList)ic.lookup("java:global/rdb/rdb.jar/List!com.lists.IList");
irc.setList(list);

On the next request, i look it up again and call getList()

InitialContext ic = new InitialContext();
IList irc = (IList)ic.lookup("java:global/rdb/rdb.jar/List!com.lists.IList");
list = irc.getList();

Note: I've changed the class names and method names and the look up name because i cannot show you the actual code.

No errors are logged. Debugging the code showed me that the data is not available.

I have another stateful bean on my system and it was coded exactly the same, and that works. Not sure why this isn't working.

score 0 · Answer 1 · answered Jun 12 '15 at 14:20

0

Each time you perform programmatic JNDI lookup on a stateful EJB bean you recieve brand new instance of that EJB. It means that in your case it works as expected. What you need to do is to store a refence to your SFSB somewhere e.g. inside HttpSession object. Then on the subsequent request you get the same SFSB instance as you got on previous request.

I have another stateful bean on my system and it was coded exactly the same, and that works

It's very interesting. Are you sure they are coded exactly the same? Can you share a piece of code?

answered Jun 12 '15 at 14:20

slwk

587
3
7

I am 100% certain, it is identical to this. The difference is only in class name and its method names. also, i haven't stored it inside the HttpSession. clarification: doesn't the container keep the stateful beans in its bean pool and return the exact bean created earlier if the same client looks it up again. refer this question http://stackoverflow.com/questions/5153012/conversational-state-of-session-beans – lego.warrior Jun 12 '15 at 16:40
No, stateful beans are not pooled. – slwk Jun 15 '15 at 06:59
so, is it not possible to implement my scenario without storing a reference to the interface in a session ? – lego.warrior Jun 15 '15 at 09:40
I doubt it is possbile without storing somehweere (eg. session). Btw, can you show the code from that another stateful bean? – slwk Jun 16 '15 at 10:34

Jboss 6.3: Stateful bean: cannot get the container to hold conversational state

1 Answers1