ISSUE 10: State sharing between ServiceReference and type-safe reference

["Barack, Ron" <ron.barack@sap.com>]

 http://www.osoa.org/jira/browse/JAVA-10

-----Ursprüngliche Nachricht-----
Von: Simon Nash [mailto:NASH@uk.ibm.com] 
Gesendet: Mittwoch, 26. September 2007 15:02
An: sca-j@lists.oasis-open.org
Betreff: [sca-j] NEW ISSUE: State sharing between ServiceReference and type-safe reference

TARGET:

Java Common Annotations and APIs specification, section "Java API" / 
{"ComponentContext", "CallableReference"}

DESCRIPTION:
 
When a ServiceReference has been created from a type-safe reference 
(proxy) using ComponentContext.cast(), or when a type-safe reference 
(proxy) has been created from a ServiceReference using 
CalllableReference.getService(), it is not clear whether actions that 
change the state of the ServiceReference also affect calls through the 
type-safe reference (proxy).

For example, in the following code snippet, where OrderService and 
DeliveryService are both conversational,

class MyClient {
    @Context ComponentContext context;
    @Reference OrderService orders;

    void createOrder(String orderID, String customerID) {
        ServiceReference<OrderService> serviceRef = context.cast(orders);
        serviceRef.setConversationID(orderID);
        orders.create(customerID);
    }

    void scheduleDelivery(String orderID, String customerID) {
        ServiceReference<DeliveryService> serviceRef = 
context.getServiceReference(DeliveryService.class, "Deliveries");
        DeliveryService deliveries = serviceRef.getService();
        serviceRef.setConversationID(orderID);
        deliveries.schedule(customerID);
    }
}

it is not clear whether either or both of the conversationID values passed 
on the setConversationID() calls will be used for the conversations that 
are started by the orders,create() and deliveries.schedule() calls.

PROPOSAL:

For the createOrder case, the cast() method should result in state that is 
shared between the ServiceReference and the type-safe reference (proxy). 
This shared state comprises the conversationID for the next conversation, 
the callback ID for the next call, and the callback object for the next 
call.

For the scheduleDelivery case, the getService() method should result in 
state that is shared between the ServiceReference and the type-safe 
reference (proxy).  This shared state comprises the conversationID for the 
next conversation, the callback ID for the next call, and the callback 
object for the next call.






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