IBM WebSphere Adapters User Manual page 77

changes. For outbound requests, the adapter must interpret the change summary,
making all applicable changes to the data. For example, if an ORDER_LINE has
been added to an ORDER object, the ORDER_LINE will appear as Created in the
change summary. The adapter is responsible for finding that ORDER, and adding
the ORDER_LINE to it.
Verbs
A verb is a property of a business graph.
If the data object being processed by the adapter has no business graph, there will
be no verb.
The AppplyChanges function, when passed a business graph, can perform either an
afterimage function or a delta update. If the verb is populated, the adapter will
perform the operation indicated by the verb. If no verb is present, the change
summary will be used to perform a delta update.
When encountering a delta business object, a component can introspect the change
summary to determine what actually occurred.
Verbs versus operations
Verbs and operations are similar conceptually but serve different purposes.
Operations reflect the functions that an adapter can perform. An operation is
directly related to the adapter performing it. By contrast, a verb is directly related
to the business object in which it is specified. In general, the verb defined for a
business object should match the operation but not always; some operations are
unrelated to the verb.
An example helps illustrate the difference between verbs and operations. If you
wanted to create a new entity in the EIS using an after-image business object, you
would specify an object verb of Create. Accordingly, a Create operation would
invoke the adapter. If you invoke an adapter Delete operation with an object that
had a Create verb, the adapter would report an error.
However, some operations, specifically those that do not fall under Create, Update,
or Delete, do not require verbs. For example, the Retrieve operation of adapters,
which has the adapter query the EIS to find an entity that matches the business
object, does not expect a verb. This Retrieve operation is unconcerned with what
action lead to the business object being created (the information reflected by the
verb); rather it is concerned only with retrieving an EIS entity that is reflected by
the object.
Note: The only time verbs are part of adapter processing is when the object has a
business graph, and the function used is applyChanges. In that case, and only that
case, the verb dictates the processing to be performed by adapter.
Business object standards
Business object naming:
EIS object names are extracted during the metadata import process. These names
often must be modified for use with a resource adapter. Business object names,
such as Customer or Address, must reflect the data structures they represent and
follow a camel case initial capitalization format.
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WebSphere Adapter development overview