Enterprise JavaBeans


Enterprise JavaBeans

(specification, business, programming)(EJB) A server-sidecomponent architecture for writing reusable business logicand portable enterprise applications. EJB is the basis ofSun's Java 2 Platform, Enterprise Edition (J2EE).

Enterprise JavaBean components are written entirely in Javaand run on any EJB compliant server. They are operating system, platform, and middleware independent, preventingvendor lock-in.

EJB servers provide system-level services (the "plumbing")such as transactions, security, threading, andpersistence.

The EJB architecture is inherently transactional,distributed, multi-tier, scalable, secure, and wire protocol neutral - any protocol can be used: IIOP,JRMP, HTTP, DCOM etc. EJB 1.1 requires RMI forcommunication with components. EJB 2.0 is expected to requiresupport for RMI/IIOP.

EJB applications can serve assorted clients: browsers, Java,ActiveX, CORBA etc. EJB can be used to wrap legacy systems.

EJB 1.1 was released in December 1999. EJB 2.0 is indevelopment.

Sun claims broad industry adoption. 30 vendors are shippingserver products implementing EJB. Supporting vendors includeIBM, Fujitsu, Sybase, Borland, Oracle, andSymantec.

An alternative is Microsoft's MTS (Microsoft Transaction Server).

http://java.sun.com/products/ejb/.

FAQ.