I just made up some questions that might be of use to some of you folks that would like to refresh the concepts... It will be nice if we can all dump sample questions in a specific, acceptable format in one location for easy reference in the future. That will serve as a mock-questions repository of some sort. Those of you can think or have come across any sample questions, please feel free to add to this. -Sridhar-
1. What type of firewall will you use to the validate the application protocol of a network communication? a. SSL b. Packet Filters c. Stateful packet Filters d. Proxy 2. Which of the following is an optional step in establishing an SSL handshake? a. Server side certificate validation by the client b. client side certificate validation by the server c. Generation of session keys for encryption and decryption d. Selection of a suitable Cipher suite for encryption by the server and the client 3. Which of the following is true about SSL a. SSL can be configured only on port 80 b. SSL can be configured only on port 443 c. SSL can be configured to work on any port above 1024 d. None of the above 4. Which of the following are true about load balancing methods?
a. DNS round robin method maps multiple IPs to a single host name b. Hardware load balancing maps multiple IPs to a single host name c. Hardware load balancing can potentially involve a single point of failure d. DNS round robin is easy to setup than hardware load balancing. e. DNS load balancing supports server affinity f. Hardware load balancing supports server affinity 5. Which of the following are true about SSL? a. SSL facilitates secure communication b. SSL is a high level protocol and sits on top of HTTP c. SSL is a low level protocol and sits below HTTP d. SSL works only with HTTP 6. Which of the following is true about aggregation and composition? a. Aggregation is a special type of composition b. Composition is a special type of aggregation c. Aggregation is represented in UML as a solid diamond d. Composition is represented in UML as a solid diamond 7. Which of the following is true about HTTP? a. HTTP is stateless b. HTTP maintains state information between requests c. HTTP is connectionless d. HTTP is connection oriented 8. In Java, String pool is an example of which OO design pattern a. Abstract Factory b. Builder c. Facade d. Flyweight 9. Select the correct sentences from below a. In the mediator pattern the individual Objects participating in the collaboration maintain direct references to each other b. Facade pattern is used to provide a simple interface to a subsystem comprising of a large number of objects. c. Memento pattern preserves Encapsulation boundaries whil exposing an object's internal state d. State pattern is used for operations that have large number of conditional statements based on the Object's state 10. Windoze Inc has the following application scenario. There is a CORBA based Enterprise Information System that generates XML based reports from the data in the backend Database storage. The application middle tier comprises of CGI and Perl scripts that are responsible for transforming the XML based report into a user-readable HTML format. The requests for the web pages come from outside users over the internet. Which of the following J2EE technology will be most suited for designing the application middleware? a. Use EJB and servlets/JSP b. Use JDBC and Servlets/JSP c. Use Servlets/JSP d. All of the above 11. Which of the following are true about UML modeling? a. UML permits representation of only ternary relationships between classes b. UML permits representation of n-ary relationships between classes and 'n' can be any arbirary number c. UML is a proprietary standard 12. Which of the following are true about encryption techniques? a. Most commercial security products use the Prime Number Factorization techniques for generating the public and private key pairs b. Public key cryptography is a more process intensive operation than symmetric key cryptography c. Elliptic curve cryptography techniques require smaller encryption keys than that required for prime factorization, to provide an equivalent degree of Encryption strength d. Elliptic key cryptography technique is a time tested method of encryption. 13. Which of the following are true about the Observer pattern ... a. The subject is the publisher of the message and the Observer is the subscriber of the message notification b. Observers can be dynamically added. c. The Observer pattern supports broadcast communications d. It promotes loose coupling between senders of messages and receivers of messages during communication e. None of the above 14. An Iterator pattern provides which of the following features. a. Access to an Aggregate object's contents b. Multiple traversals of aggregate objects c. an uniform interface for traversing different aggregate structures through polymorphism d. all of the above e. none of the above 15. Which of the following is used for deferring creation of expensive objects? a. Proxy b. Abstract Factory c. Abstract method d. Builder [ March 04, 2002: Message edited by: Sridhar Raman001 ] [ March 05, 2002: Message edited by: Sridhar Raman001 ] [ March 05, 2002: Message edited by: Sridhar Raman001 ] [ March 16, 2002: Message edited by: Sridhar Raman001 ]
16. Which of the following are true about the Primary Key class in Entity EJB? a. It is used for identifying an Entity BEan according to the Bean type, remote interface and Container Context b. It is used for identifying an Entity BEan according to the Bean type, home interface and Container Context c. The definition of the Primary Key can be deferred until deployment d. The primary key should override the equals() and hashCode() methods of the Object class e. The primary key class cannot define constructors 17. In CMP Entity Beans, which of the following statements is true? a. The Entity Bean Class should not define any constructors b. The Entity Bean class must define a no-argument constructor 18. The home interface associated with an Entity Bean a. must declare at least one create() method b. May not declare any create() methods c. must declare the findByPrimaryKey() method d. May not declare any finder methods 19. When is ejbStore() invoked? a. Immediately before the container reads the Bean's state information. b. Immediately after the containter reads the BEan's state information 20. When is ejbLoad() invoked? a. Immediately before setting the Bean's state information. b. Immediately after setting the Bean's state information 21. A CMP bean ... a. must provide only an empty implementation of ejbStore() and ejbLoad() methods b. May provide a concrete implementation of the ejbStore() and ejbLoad() methods 22. In EJB, What type of exception is thrown when a system error occurs ? a. EJBException b. RemoteException c. Exception d. BeanException 23. In EJBs, Which of the following are application exceptions? a. NullPointerException b. ObjectNotFoundException c. CreateException d. IndexOutOfBoundsException e. None of the above f. All of the above 24. Is ejbPassivate() invoked by the container when ejbRemove() is invoked? a. true b. false 25. Windoze Inc, is planning to implement an Enterprise wide integration of all their applications. They have chosen to apply the Hub-and-Spoke model of Enterprise Integration, where a central hub will facilitate all information sharing between applications, in the form of documents. Applications can post and receive documents to this central hub. Each application will register themselves with this central hub through an administrative interface. The Central hub sends notifications to the registered applications when a specific document of interest, arrives at the hub. The application upon receiving the notification may choose to download the documents. What is the most appropriate J2EE technology that can be used to implement this Enterprise Integration. a. Model the central hub as a mail server and the individual applications as JavaMail clients. b. Model the central hub as a JMS provider and individual applications as JMS clients. Use a publish-subscribe messaging domain. c. Model the central hub as a JMS provider and individual applications as JMS clients. Use a point-point messaging domain. d. Model the central hub as a Session Bean and individual applications as EJB clients.
26. MicroSucks Corp is planning to implement web based data entry application to collect information from business partners. The data received is to be transformed to a pre-defined format and dispatched from the web tier to a protected backend mail service (behind the firewall) over SMTP How will you design the web tier for this application using J2EE technology? a. Use Servlets/JSP to provide the user interfaces and accept data from the user over HTTP. Use Java classes to transform the data received from the user. Use JavaMail clients to dispatch the transformed data to the backend mail server. b. Use Session Beans to transform the incoming data. Use applets to communicate with the EJB tier over RMI-IIOP, at the client tier. Use JavaMail clients to dispatch the transformed data to the backend mail server. c. Use applets to perform the data transformation and generate a flat file at the client, after accepting data input from the user. The user can directly email this flat file to the backend mail server through a third-party email client
27. In EJBs, Which two callback methods can be used for synchronizing the bean's state with the database a. ejbStore() and ejbLoad() b. ejbActivate() and ejbPassivate() c. ejbStore() and ejbPasivate() d. ejbLoad() and ejbActivate()
28.Which type of EJBs are ideal to model multiple rows of read-only data? a. Entity Beans b. Session Beans 29. When does an Entity Bean transition from Pooled State to Ready state a. when create() is invoked on EJBHome b. when a find method is invoked on EJBHome c. when a BEan is activated by the container d. when a BEan is passivated by the container 30. When is unsetEntityContext() invoked on an Entity bean? a. When the entity bean is to be garbage collected b. After an entity bean is garbage collected c. after the finalize() method has been invoked on the EntityBean d. None of the above [ March 07, 2002: Message edited by: Sridhar Raman001 ]
Thanks, JiaPei. I guess we all share a symbiotic relationship. We take some and we give some Maggie....Wuz debating if I should post the answers but I guess I'll do it. I'll open a separate thread and provide links to it. This way the answers and questions can evolve independently...(Smells like Bridge Pattern...). Also, people can have two windows open instead of having to scroll up and down to check the answers.... Meanwhile, am posting some more questions..... -Sridhar- [ March 06, 2002: Message edited by: Sridhar Raman001 ]
31. In EJB the timeout property is defined in the deployment descriptor. a. True b. False 32. Which of the following events happen after a stateless session bean times out or when a remove() operation is invoked? a. the remote reference held by the client is invalidated b. the bean instance is destroyed c. None of the above d. All of the above 33. The create() method in the Home Interface of a Stateless Session Bean may contain arguments? a.true b.false 34. Which of the following is true about the remove(Object primaryKey) method of the EJBHome interface with respect to a stateless session bean? a. If the remove(Object primaryKey) is invoked on a stateless session bean the container ignores the method call. b. If the remove(Object primaryKey) is invoked on a stateless session bean the container throws a remote exception c. remove(Object primaryKey) is a perfectly valid operation for a stateless session bean a. The EJBHome of a stateless session bean does not have a remove(Object primaryKey) method definition
35. When does the ejbPassivate() method get invoked on a stateless bean a. Immediately after servicing a client request b. When the bean instance is transitioned from Method ready state to does not exist state c. ejbPassivate() is never invoked on a stateless session bean d. None of the above 36. Is the SessionContedt and JNDI ENC available to the bean instance during ejbREmove() operation? a. true b. false 37. Stateless Session beans are lightweight objects and offer good performance in comparison with Stateful session beans. a. True. b. False c. Depends on the implementation of the EJB container d. Depends on the implementation of the EJB server 38. Which type of EJB is ideal for application such as report generation and batch processing? a. entity beans b. Stateless session beans c. stateful session beans. d. all of the above e. none of the above 39. In Stateless session beans, the clean up code for resources such as connections,etc should be coded in which of the following methods? a. ejbRemove() b. ejbPassivate() c. ejbRemove() and ejbPassivate() d. ejbDestroy() 40. Blue Screen of Death Inc has an old order entry system that is part an integrated suite of ERP modules. In this system the business logic surrounding the Order Entry Process is encapsulated as database Stored Procedures. The company wants to web enable this Order Entry System so that their customers can search through the products catalog and place orders over the internet. Assuming that the ERP's RDBMS supports JDBC compliant drivers, how will you propose to implement a solution for this initiative using J2EE technology? a. Use Servlet and JSP for generating the web interfaces. Use Entity Beans to represent the business entities. Rewrite the business logic of the backend database stored procedures as Session Beans. b. Use Servlet and JSP for generating the web interfaces. Use Session Beans to represent the business entities. Encapsulate the business logic using Entity beans but reuse the Backend stored procedures through JDBC. c. Use Servlet and JSP for generating the web interfaces. Use Entity Beans to represent the business entities. Encapsulate the business logic using SEssion beans but reuse the Backend stored procedures through JDBC. d. Use Servlet and JSP for generating the web interfaces. Use Entity Beans to represent the business entities. Invoke JDBC calls directly from the servlet to communicate with the ERP's database
thanks for posting sample Question. it would be nice if we start giving our answer and then look for rihgt answer along some justification this would make understanding batter rather then just memorizing the possible answer... if so body likes idea please feel free to share his openion.
Sridhar Thanks for this wonderfull collection of questions but your answers are wrong. I just looked up till 5th answer and atleast 3 are wrong. 1. May be is right. 2. You read it as 'optional' where as question says 'not optional'. 3. SSL works on port 993, so D is right. 4. Ok 5. it's C Please remove/review them urgently lest others will end up confused. Aman Aggarwal
Is answer for the question 30 is correct ? 30. When is unsetEntityContext() invoked on an Entity bean? a. When the entity bean is to be garbage collected b. After an entity bean is garbage collected c. after the finalize() method has been invoked on the EntityBean d. None of the above Somebody comment pls...