Cracking the Java Coding Interview pdfdrive com

Question How can I implement a thread-safe JSP page? (JSP)
Answer You can make your JSPs thread-safe by having them implement the
SingleThreadModel interface. This is done by adding the directive <%@ page
isThreadSafe="false" % > within your JSP page.
Question Is it possible to stop the execution of a method before completion
in a SessionBean? (EJB)
Answer Stopping the execution of a method inside a Session Bean is not
possible without writing code inside the Session Bean. This is because you are
not allowed to access Threads inside an EJB.
Question What is the default transaction attribute for an EJB? (EJB)
Answer There is no default transaction attribute for an EJB. Section 11.5 of EJB
v1.1 spec says that the deployer must specify a value for the transaction attribute
for those methods having container managed transaction. In weblogic, the
default transaction attribute for EJB is SUPPORTS.

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Question What is the difference between session and entity beans? When
should I use one or the other? (EJB)
Answer An entity bean represents persistent global data from the database; a
session bean represents transient user-specific data that will die when the user
disconnects (ends his session). Generally, the session beans implement business
methods (e.g. Bank.transferFunds) that call entity beans (e.g. Account.deposit,
Account.withdraw)
Question Is there any default cache management system with Entity beans ?
In other words whether a cache of the data in database will be maintained
in EJB ? (EJB)
Answer Caching data from a database inside the Application Server are what
Entity EJB's are used for.The ejbLoad() and ejbStore() methods are used to
synchronize the Entity Bean state with the persistent storage(database).
Transactions also play an important role in this scenario. If data is removed from
the database, via an external application - your Entity Bean can still be "alive"
the EJB container. When the transaction commits, ejbStore() is called and the
row will not be found, and the transcation rolled back.