This week's book giveaway is in the Jython/Python forum.
We're giving away four copies of Murach's Python Programming and have Michael Urban and Joel Murach on-line!
See this thread for details.
Win a copy of Murach's Python Programming this week in the Jython/Python forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic

What's an EJB?  RSS feed

 
Diana Garc�a
Ranch Hand
Posts: 31
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hello all,

I'm very new to J2EE and want to know in few words what EJB is. I've read many web pages but still don't know what can I use them for.

Thank you very much
 
Vagner Freitas
Ranch Hand
Posts: 85
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi Diana,

Enterprise JavaBeans is an architecture for component-based distributed computing. Enterprise beans are components of distributed transaction-oriented enterprise applications.
The essential characteristics of an enterprise bean are:

. An enterprise bean typically contains business logic that operates on the enterprise�s data.

. An enterprise bean�s instances are created and managed at runtime by a Container.

. An enterprise bean can be customized at deployment time by editing its environment entries.

. Various services information, such as a transaction and security attributes, are separate from the enterprise bean class. This allows the services information to be managed by tools during application assembly and deployment.

. Client access is mediated by the Container in which the enterprise Bean is deployed.

. If an enterprise Bean uses only the services defined by the EJB specification, the enterprise Bean can be deployed in any compliant EJB Container. Specialized containers can provide additional services beyond those defined by the EJB specification. An enterprise Bean that depends on such a service can be deployed only in a container that supports that service.

. An enterprise Bean can be included in an assembled application without requiring source code changes or recompilation of the enterprise Bean.

. The Bean Provider defines a client view of an enterprise Bean. The Bean developer can manually define the client view or it can be generated automatically by application development tools. The client view is unaffected by the container and server in which the Bean is deployed. This ensures that both the Beans and their clients can be deployed in multiple execution environments without changes or recompilation.

I hope it help you.

Vagner
 
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!