How the adapter works

The adapter for CES Centricity Gateway is bidirectional. It can process events originating from the CES Centricity applications, as well as requests sent by the integration broker to the application. The following sections overview this process.

Processing events

This section briefly describes how the adapter processes application events.

Event detection

Events are detected by the queue-based transport using polling. The transports poll the queue at a user-specified interval looking for events. When an event is found, the transport examines the queue to see the next message and removes the event after it is added to the adapter event store.

Event notification

All event notification is handled by the WBI transport and the queue-based transports. See Event life cycle for a summary of the processing that occurs.

Request processing

The adapter for CES Centricity Gateway processes the requests coming from the integration broker in the form of business objects. The business objects are received from the integration broker by the WBIReceiver transport, where they are translated into XML representation by the data handler. XSLT processing is then performed to convert the XML business object representation into a CES Centricity Gateway request. The XML is then delivered to the application by the application transport component. If necessary, a response code and business object is delivered to the WBIReceiver component to populate the response object.

The queue-based transports provided with the adapter framework also handle synchronous event retrieval. Events are considered synchronous if the business object verb is in the list of verbs in the expectReplyOnVerb parameter. A user-specified timeout (replyTimeout parameter) is provided that indicates how long the sender should wait for the synchronous reply to arrive on a receiver queue before indicating an error occurred. Upon detection of the error, the sender logs an appropriate message and returns an application response timeout error code to the broker. If any exception occurs during the process of sending the request and receiving the response, the transport logs all error information and notifies the broker accordingly. See Event store file naming for a list of status and error constants that may be returned. See Event life cycle for a summary of the processing that occurs.

Copyright IBM Corp. 1997, 2003