Interview Tutorials
101. Interview Question: What are the call back methods in Entity bean?
By: Ash : 2008-08-13
Description: Callback methods allows the container to notify the bean of events in its life cycle. The callback methods are defined in the javax.ejb.EntityBean interface.
102. Interview Question: What is Message Driven Bean?
By: Ash : 2008-08-13
Description: An MDB is essentially a message consumer that can listen to a message destination or a message endpoint and gets activated when a message arrives. By design, MDBs are anonymous in nature and hence cannot be directly invoked by a client.
103. Interview Question: What is local interface. How values will be passed?
By: Ash : 2008-08-13
Description: An EJB can use local client view only if it is really guaranteed that other enterprise beans or clients will only address the bean within a single JVM.
104. Interview Question: What is abstract schema?
By: Ash : 2008-08-13
Description: Abstract schema is part of an entity bean's deployment descriptor which defines the bean's persistent fields and their relationship. Abstract schema is specified for entity beans with container managed persistence.
105. Interview Question: What is the difference between JavaBean and EJB?
By: Ash : 2008-08-13
Description: A Java Bean is a software component written in the Java programming language that conforms to the JavaBeans component specification. The JavaBeans APIs became part of the "core" Java APIs as of the 1.1 release of the JDK.
106. Interview Question: What is the difference between find and select methods in EJB?
By: Ash : 2008-08-13
Description: A select method can return a persistent field (or a collection thereof) of a related entity bean. A finder method can return only a local or remote interface (or a collection of interfaces).
107. Interview Question: Is it possible to share an HttpSession between a JSP and EJB? What happens when I change a value in the HttpSession from inside an EJB?
By: Ash : 2008-08-13
Description: You can pass the HttpSession as parameter to an EJB method, only if all objects in session are serializable.This has to be consider as passed-by-value, that means that it's read-only in the EJB.
108. Interview Question: What is the difference between Message Driven Beans and Stateless Session beans?
By: Ash : 2008-08-13
Description: In several ways, the dynamic creation and allocation of message-driven bean instances mimics the behavior of stateless session EJB instances, which exist only for the duration of a particular method call.