Data mapping
is the process of transforming (or mapping) data from one
application-specific format to another. Mapping is central to the
process of transferring information between different applications, and for
providing collaborations (business processes) that are independent of specific
applications. By mapping data between
application-specific business objects and
generic business objects, WebSphere creates the environment that allows for
the use of "best of breed" applications. The WebSphere business
integration system provides a modular and extensible architecture for easy
maintenance of your maps.
The WebSphere map development system provides comprehensive support for
mapping between business objects, including the following capabilities:
- Transforming data values from one or more attributes in a source business
object to one or more attributes in a destination business object
- Establishing and maintaining relationships between data entities that are
equivalent but are represented differently and cannot be directly transformed
- Enabling access to external mapping resources, such as third-party mapping
products and databases for performing queries
When data mapping is set up among differing applications, an event
occurrence in one application is performed in any other application to which
it is mapped. An event occurrence can be when data is created,
retrieved, updated, or deleted.
Mapping uses
maps that define the transfer (or transformation) of data between
the
source and
destination business objects. In the map development environment, data
is mapped from an application-specific business object to a generic business
object or from a generic business object to an application-specific business
object. Table 1 lists the types of mapping required.
Table 1. Mapping requirements
Direction of business object
| Source business object
| Destination business object
| Type of map
|
Connector to collaboration
| Application-specific
| Generic
|
Inbound map
|
Collaboration to connector
| Generic
| Application-specific
|
Outbound map
|
Figure 1 illustrates how mapping occurs at run time, using a
fictionalized Employee Management collaboration as an example.

Figure 1. Data mapping at run time
The Employee Management collaboration (Collaboration1) receives
an Employee business object from the source connector (App
A), then sends an Employee business object to the destination
connector (App B). Figure 1 illustrates the following sequence occurs (the numbers here
correspond to the numbers in the figure):
- An event occurs in App A. The App A connector
produces an App A Employee business object and sends it to the
App A connector controller.
- The App A connector controller sends the App A
Employee business object to the Employee Management collaboration
(Collaboration1), which resides on InterChange Server Express, for
mapping. The request includes the name of the data map that the server
must use, based on the map name specified in the connector
configuration.
- The
inbound map returns the generic Employee business object to the
App A connector controller.
- The App A connector controller checks the collaborations that
have subscriptions to the generic Employee business object.
In this case, Collaboration1 has a subscription, so the connector
controller hands the business object to Collaboration1.
- The collaboration performs some processing, then produces another generic
Employee business object as output, which it sends to the App
B connector controller.
- The App B connector controller sends the generic business
object to InterChange Server Express, requesting mapping to the App B
Employee business object.
- The
outbound map returns the application-specific Employee business
object to the App B connector controller.
- The App B connector controller passes the App B
Employee object to the App B connector, which can then pass
the data in the business object into App B.
The figure shows two types of maps in use:
- One inbound map from the App A Employee business object to the
generic Employee business object used by the collaboration
- One outbound map from the generic Employee business object to
the App B Employee business object
The Employee data moves in only one direction--from Application A
toward Application B. If you want to exchange the Employee data in both
directions between both applications, two more maps are required:
- An inbound map from the application-specific business object of
Application B to the generic business object
- An outbound map from the generic business object to the
application-specific business object of Application A
