javax.enterprise.context

Annotation Type ConversationScoped

@Target(value={TYPE,METHOD,FIELD})
@Retention(value=RUNTIME)
@Documented
@NormalScope(passivating=true)
@Inherited
public @interface ConversationScoped

Specifies that a bean is conversation scoped.

The conversation scope is active:

• during all standard lifecycle phases of any Servlet request.

The conversation context provides access to state associated with a particular conversation. Every Servlet request has an associated conversation. This association is managed automatically by the container according to the following rules:

• Any Servlet request has exactly one associated conversation.
• The conversation associated with a Servlet request is determined at the beginning of the request and does not change during the request.

Any conversation is in one of two states: transient or long-running.

• By default, a conversation is transient
• A transient conversation may be marked long-running by calling Conversation.begin()
• A long-running conversation may be marked transient by calling Conversation.end()

All long-running conversations have a string-valued unique identifier, which may be set by the application when the conversation is marked long-running, or generated by the container.

If the conversation associated with the current Servlet request is in the transient state at the end of a Servlet request, it is destroyed, and the conversation context is also destroyed.

If the conversation associated with the current Servlet request is in the long-running state at the end of a Servlet request, it is not destroyed. The long-running conversation associated with a request may be propagated to any Servlet request via use of a GET request parameter named cid containing the unique identifier of the conversation. In this case, the application must manage this request parameter.

If the current Servlet request is a JSF request, and the conversation is in long-running state, it is propagated according to the following rules:

• The long-running conversation context associated with a request that renders a JSF view is automatically propagated to any faces request (JSF form submission) that originates from that rendered page.
• The long-running conversation context associated with a request that results in a JSF redirect (a redirect resulting from a navigation rule or JSF NavigationHandler) is automatically propagated to the resulting non-faces request, and to any other subsequent request to the same URL. This is accomplished via use of a GET request parameter named cid containing the unique identifier of the conversation.

When no conversation is propagated to a Servlet request, the request is associated with a new transient conversation. All long-running conversations are scoped to a particular HTTP servlet session and may not cross session boundaries. In the following cases, a propagated long-running conversation cannot be restored and reassociated with the request:

• When the HTTP servlet session is invalidated, all long-running conversation contexts created during the current session are destroyed, after the servlet service() method completes.
• The container is permitted to arbitrarily destroy any long-running conversation that is associated with no current Servlet request, in order to conserve resources.

Author:

Gavin King, Pete Muir

See Also:

Conversation, NonexistentConversationException, BusyConversationException