Sunday, November 01, 2009

EJB Container and Features of EJB Container

EJB container : It program that runs on the server and provides environment for running the enterprise components. Enterprise beans are used in distributed applications that typically contains the business logic

Features of EJB Container :-
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1.Transaction Management :
Support for Transaction.It uses the Java Transaction APIs(JTA) to expose the transaction services. JTA, interface which is used to control transactions.

2.Security:
Uses JSE to make more secure app. Enterprise beans add this feature to provide transparent security.

3.Remote Accessibility:
Client(remote) can invoke enterprise bean running on host machine using RPC Remote Procedure Call .Basically RMI- Remote Method Invocation concept.


4.Resource and Life Cycle Management:
It manages resources like database connections, threads and socket on behalf of enterprise beans and creates, destroys, registers the objects,reusing them also.

5.Collision:
This can occur when two or more transactions tries to change the entities within a system of records. 3 types are : 1.Dirty read 2.Non Repeatable read 3.Phantom read

6.Clustering and load-balancing:
Clustering is process of combining the multiple peripherals, computers and other resources into a single unit. A clustered system then works as load balanced system. In a distributed system when a request is send to the server, an algorithm running on the server decides which server has less load and sends the request to that server.

7.Concurrency Control
Optimistic Locking
Pessimistic Locking

Author : Anuj Patel
Blog : http://goldenpackagebyanuj.blogspot.in/