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Chapter 15: Entity Beans and Table Mapping for CMP 2.0 149
Chapter
15
Chapter 15Entity Beans and Table Mapping
for CMP 2.0
Here we'll examine how entity beans are deployed in the Borland Enterprise
Server and how persistence of entities can be managed. This is not, however,
an introduction to entity beans and should not be treated as such. Rather, this
document will explore the implications of using entity beans within Borland
Partitions. We'll discuss descriptor information, persistence options, and other
container-optimizations. Information on the Borland-specific deployment
descriptors and implementations of Container-Managed Persistence (CMP)
will be documented in favor of general EJB information that is generally
available from the J2EE Specifications from Sun Microsystems.
Important For documentation updates, go to www.borland.com/techpubs/bes.
Entity Beans
Entity beans represent a view of data stored in a database. Entity beans can
be fine-grained entities mapping to a single table with a one-to-one
correspondence between entity beans and table rows. Or, entity beans can
span multiple tables and present data independent of the underlying database
schema. Entity beans can have relationships with one another, can be queried
for data by clients, and can be shared among different clients.
Deploying your Entity Bean to one of the Borland Enterprise Server Partitions
requires that it be packaged as a part of a JAR. The JAR must include two
descriptor files: ejb-jar.xml and the proprietary ejb-borland.xml file. The ejb-