Saturday, February 14, 2009

SCEA 5.0 - Exam Questions - 3

Few more questions for the exam:

31. Which two can be used to maintain convesational state ? (Choose two.)

A. Entity beans
B. Http session
C. Stateful session beans
D. message-driven beans
E. stateless session beans

Correct B,C

32. You are the architect of a project that will provide an external, low latency, scalable, and highly- available sevice for handling string transactions. Each request consists of a short string ID and laguage key, limited to "EN", "FR", "ES", "DE", and "JP". Each response is a simple unicode string averaging 256 bytes in size, and there will be no more than 50,000 records for each language. All the records have aleady been translated and changes to the records will be rare.

What should you do to ensure that your service wll scale and perform well as new clients are added ?
A - store all the records in an LDAP server and use JNDI to access them from the web tier
B - deploy a standard 3-tier solution that is supported by a fast and reliable relational database
C - deploy a single service on many servers in the web tier, each storing all the records in memory
D - store all of the records in a network attached file system so they can be served directly from the file system

Correct: C

33.Tou are the architect of a web application that uses JSF as a presentation tier for business processes coded as stateless session beans. When you add new code to the stateless session beans to address new accounting requirements, without changing the interface, you discover that the new business processes are being ignored by some of the JSF components.

Which might be the cause of this problem?
A - The presentation tier is relying on validation logic in the business tier.
B - The broswer is caching out-of-date versions of the JSF components.
C - The business processes are not rigorously encpsulated in the session beans.
D - The new session beans have been deployed incorrectly, and proper deployment will resolve the problem.

Correct: C

34. You have refactored your legacy Java application into a three-tiered architecture. Your security audit group is concerned that your architecture may be vulnerable to security threats in the separate tiers. Which two methods can you use to reduce those threats? (Choose two).

A - programmatic security in the EJB entities
B - interecepting filters between the view and the controller
C - intercepting filters between the controller and the model
D - role-based security for the EJBs in the deployement descriptor

Correct: B,D

35. Drag and drop the question. Drag the items to the proper locations.

Correct:

36. The current architecture of a fashion website consists of one web server, three application servers, and a database. You, as the lead architect, recommend adding more web servers. What are two valid justifications for new architecture? (Choose two.)
A. New web servers will decrease latency for I/O-bound requests.
B. Adding multiple web servers will have a positive impact on scalability.
C. Adding new web servers will increase the overall availability of the web site.
D. New web servers will increase the number of user accounts that can be supported.
Correct: B,C
37. Which three statements are true about delegation as on OO design technique? (Choose three.)
A. It is applied to a system only at compile time.
B. It is an essential element of the State pattern.
C. It is an essential element of the Singleton pattern.
D. It allows you to replace inheritance with composition.
E. In Java technology, it is always implemented through the use of generics.
F. It always requires that at least two objects are involved in handling a request.
Correct: B, D, F
38. Which two statements are true about the Flyweight pattern? (Choose two.)
A. It allows a single instance of a class to virtually represent many instances.
B. When used approximately it can reduce memory demands on your servers.
C. It allows for many instances of a class to be controlled by a single instance.
D. It allows many tightly related, homogeneous objects to each maintain their own state.
Correct: A, B
39. Which two techniques can used to provide polymorphic behavior? (Choose two.)
A. extending a class and adding a new method
B. implementing two interfaces in the same class
C. extending a class and overriding an existing method
D. implementing an interface with several different classes

Correct: C, D

40. As a project architect, you are selecting technologies for a complex, n-tier web application's virtual platform. At this stage in the project, which two technologies should be of primary consideration? (choose two.)

A. RMI
B. Linux
C. JDBC
D. Firefox
E. Tomcat

Correct: A, C