WAS v8.5 > Reference > Developer detailed usage informationWebSphere extensions to the Enterprise JavaBeans specification
This topic outlines extensions to the Enterprise JavaBeans (EJB) specification provided with the product.
Inheritance in enterprise beans
In the Java language, inheritance is the creation of a new class from an existing class or a new interface from an existing interface. WAS v8.5 supports two forms of inheritance: standard class inheritance and EJB inheritance.
In standard class inheritance, the home interface, remote interface, or enterprise bean class inherits properties and methods from base classes that are not themselves enterprise bean classes or interfaces.
By contrast in enterprise bean inheritance, an enterprise bean inherits properties, such as container-managed persistence fields and container-managed relationship (CMR) fields, methods, and method-level control descriptor attributes from another enterprise bean.
For more information, see the documentation for the assembly tools.
Optimistic concurrency control for container-managed persistence
WAS v8.5 supports optimistic concurrency control of data access. For more information, see the topic about concurrency control.
Access intents for EJB persistence
WAS v8.5 supports the application of named data-access policies.
Sequence grouping for container-managed persistence
By designating CMP sequence groups for entity beans, we can prevent certain types of database-related exceptions from occurring during the run time of custom EJB application. Within each group we specify the order in which the beans update your relational database tables. For instructions, see the topic about setting the run time for CMP sequence groups.
Performance enhancements
Through the lifetime-in-cache settings, this product provides a way for you to improve performance for beans that are only occasionally updated. For more information, see the topic about entity bean assembly settings in the assembly tool documentation.
Some enterprise beans created with the assembly tools can utilize read-ahead for loading a bean and its related beans in a single database operation. An entire object graph or any part of the graph can be preloaded by configuring a finder method to use read-ahead.
Assembly and deployment extensions
WAS v8.5 supports IBM extensions of assembly and deployment options.
Related concepts:
Development and assembly tools
Concurrency control
Access intent policies for EJB 2.x entity beans
Read ahead scheme hints
Sequence grouping for container-managed persistence in assembled EJB modules
Related
Set the run time for CMP sequence groups
Develop enterprise beans
Assemble EJB modules
Related information:
Rational Application Developer documentation