beautypg.com

Callback event sender – IBM WebSphere Adapters User Manual

Page 97

background image

Using the IBM WebSphere adapter foundation classes for
inbound callback event processing

The adapter foundation classes can automatically track endpoints (the consumers
of events) for the adapter, control the event pick up and delivery of events, handle
recovery of events if the adapter unexpectedly terminates, and assure
once-and-only-once event delivery.

This allows developers to provide greater quality of service (QoS) in less time and
also ensure that behavior across adapters is consistent.

Although not required, it is a recommended practice that you use IBM WebSphere
adapter foundation classes (AFC) for adapters that have to provide callback event
notification.

Adapter foundation classes make the process of callback event delivery in an
assured manner easier for the developer creating the adapter, by providing the
event delivery API called the CallBackEventSender.

The following diagram depicts the usage of adapter foundation classes (common
component). The CallbackEventSender API is integral to the adapter foundation
classes.

EIS

Adapter

Callback
From EIS

Message

Delivery (with

optional return)

Client

system

Response

Response

C
o
m
m
o
n

C
o
m
p
o
n
e
n
t

C
a
l
l
b
a
c
k

Callback event sender

CallbackEventSender in com.ibm.j2ca.extension.eventmanagement.external package
provides four public methods.

CallbackEventSender in com.ibm.j2ca.extension.eventmanagement.external
package provides following four public methods.

v

public void sendEventWithNoReturn(Record, InteractionSpec) throws
WBISendFailedException

v

public Record sendEventWithReturn(Record, InteractionSpec) throws
WBISendFailedException

v

public void sendEventWithNoReturn(GenericEvent, Record, InteractionSpec)
throws WBISendFailedException

v

public Record sendEventWithReturn(GenericEvent, Record, InteractionSpec)
throws WBISendFailedException

These methods end up invoking different methods in the message-driven bean
(MDB). The MDB will implement several interfaces, including InboundListener,
and MessageListener.

WebSphere Adapter development overview

91