Entity EJB

• Purpose
• Structure
• Applications
• Consequences

Purpose

• To express/save business domain data and configure relationships with databases.
• To enable data synchronization and transaction services.

Structure

• EntityBean : EJB for expressing business-related data.
• Entity : Remote Interface for EntityBean.
• EntityHome : Home Interface for EntityBean.
• EntityPK : Class for identifying EntityBean.

Applications

• Can be used for applying Object-Relation Mapping to business domain data.
• Can be used for assuring the synchronization, transaction and integrity of the data.

Consequences

• Data Access layer expresses persistent objects.
• Data synchronization and transaction integrity can be guaranteed by delegating to containers.
• In case of data structure change, only the related EntityBeans need to be modified.