Glossary

A storage medium that holds information permanently regardless of whether the computer is powered (e.g. a hard disk).

Used to prevent tasks from being concentrated to one side in clustering.

The main memory of the computer is also known as runtime memory or RAM, standing for Random Access Memory.

A contrary concept to inactivation (or passivation). Indicates that a bean instance is moved from the secondary storage to the runtime memory.

Indicates that email is automatically transmitted in an abnormal situation in JEUS.

A pool of EJB instances.

Either of J2EE basic bean type (e.g. stateless, stateful, entity and message-driven bean) or a bean defined by a developer (a sub bean of the basic J2EE bean).

Bean-managed persistence entity bean.

Container-managed persistence entity bean.

Pool of EJB objects. These objects are responsible for connecting a client to EJB and communicating.

An abbreviation of deployment descriptor.

Enterprise Java Beans.

The settings of EJB beans which are distributed in multiple EJB engines. It may look like a bean from the client side, but internally loads are balanced for improving stability and performances.

A component using an EJB method (e.g. an independent Java application, Servlet or another EJB)

"EJB container" in the J2EE specification. This provides a fundamental environment of the EJB component.

Used to improve stability by using multiple engines which execute the same EJB application.

One EJB package in EJB JAR, or more. An EJB deployed to an EJB engine uses the EJB module.

A special cache used to keep inactivated ones in entity beans. Only when this cache is full, those beans are inactivated to the secondary storage. Entity cache is used for performance improvement.

Message Driven Bean.

Refer to 'connection pool' and 'bean pool environment'.

To move an EJB instance from the runtime memory to the secondary storage until requested.

It is the same as the queue data structure, and selected from the one that entered the queue earlier. This guarantees fair load-balancing for each component.

Stateful Session Bean.

Stateless Session Bean.

A pool of access tickets. To access an EJB from JEUS, the client must obtain “thread ticket” from the thread ticket pool.