[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]
Subject: Fw: [sca-j] ISSUE 25 - Callback Simplification
"Michael Rowley"
<mnrowley@gmail.com>
03/04/2008 15:40
|
|
I like the fact that, in Simon's model, callbacks always go back to the instance that made the outbound call. However, it looks like he does not take advantage of that fact in the interfaces of the examples that he created. For example, he has the following:
@Callback(OrderCallback.class)
public interface Order {
void placeOrder(String orderID, String orderData);
}
public interface OrderCallback {
void confirm(String orderID);
void update(String orderID, String status);
}
However, since you know that the order callback goes back to the right instance, you should be able to define the callback interface as follows:
public interface OrderCallback {
void confirm();
void update(String status);
}
In Simon's model this should be possible, but there is a catch. If the callback interface is defined this way, the client has to use a conversational scope. If the client is stateless or composite scoped, then the routing of the callback to the right instance doesn't say anything useful about what is being confirmed.
I would like to enable this style of callback interface irrespective of the scope of the client. As with Simon's approach, if the client is conversational scoped, then the client is especially simple and does not have to do any correlation at all. However, if the client needs to use some other scope, for whatever reason, then the service with the callback can still be used. However, it just needs to get the callback ID (or conversation ID) that is associated with the callback in order to determine what the callback is talking about.
Michael
From: Simon Nash [mailto:NASH@uk.ibm.com]
Sent: Thursday, March 27, 2008 11:47 AM
To: sca-j@lists.oasis-open.org
Subject: Re: [sca-j] ISSUE 25 - Callback Simplification
There's an update to this proposal at
http://www.oasis-open.org/apps/org/workgroup/sca-j/download.php/27733/JAVA-25-Proposal-2.doc
This version removes conversational callbacks as all my attempts to define
these involve more complexity than is justified by the functional value
of this capability.
Simon
Simon C. Nash, IBM Distinguished Engineer
Member of the IBM Academy of Technology
Tel. +44-1962-815156 Fax +44-1962-818999
Simon Nash/UK/IBM@IBMGB
20/03/2008 11:01 |
|
Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number
741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6
3AU
Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number
741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6
3AU
Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number
741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6
3AU
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]