Enterprise Java Beans - EJB MCQ Questions Answers

1. Which of the following statements is not correct for an Enterprise Java Bean?

2. The following method signature is found in an implemented entity bean named 'CustomerBean.' 'CustomerPK' is a class representing the primary key.

public CustomerPK ejbFindByPrimaryKey(CustomerPK key)
                throws FinderException

By context look up, a client gets the reference to the home object of the above bean, named 'custHome'. It gets the 'CustomerPK' class named 'PK' by a different method. The name of EJBObject is 'Customer', which represents a customer. Which of the following options will you select to invoke the above mentioned method in the client?

3. Which of the following statements is not correct with regard to Passivation of beans?

4. Which of the following transaction modes are supported by Enterprise Java Beans?

5. Which of the following statements is correct with regard to entity, session, and message-driven beans?

6. What are the three classes that a Session EJB class must provide?

7. One of the methods of your entity bean retrieves the names of all the patients admitted in a particular ward of a hospital. Using a connection named 'con', you want to execute the following query:

//secId is the parameter received by the method
String query = "SELECT admissionId, patientFirstName, patientLastName FROM ADMISSION WHERE sectionId=" + secId;

Which of the following options will help you execute the query?

8. SessionSynchronization Interface must be implemented to reset the instance variables.

9. To disable the Passivaton process, set the EJBPassivationTimeout() variable to zero.

10. Database connection pooling is beneficial because:

11. Both RMI and CORBA define messaging protocols called:

12. You are working with EJB2.0. You have to retrieve a previously saved handle to an EJBObject named 'bookEJBObject.' In order to restart the processing for that particular request, you need to get the remote interface. The following code has been written for the same:

1. ObjectInputStream stream =
2.                new ObjectInputStream(new FileInputStream(fileName));
3.
4. Handle bookHandle = (Handle) stream.readObject();
5.
6. BookRemoteInterface bookEjbObject = (BookRemoteInterface) XX() ;

Which of the following should substitute Method XX() of line 6?

13. The EJB specification defines six distinct roles in the application development and deployment life cycle. Which of the following roles is not mentioned in it?

14. Which of the following constitute the enhancements made to EJB 2.0?

15. Which of the following statements is not correct with regard to relationships in EJB?

16. Which of the following is not implemented by a stateless session bean?

17. You don't have any database recovery/backup system in place. Which of the following statements is true with regard to committed and uncommitted data of your entity bean?

18. Which of the following statements is correct with regard to JavaBeans and Enterprise JavaBeans?

19. Which of the following services does EJB container provide to a bean?

20. The transaction attribute of a bean is set to 'TX_REQUIRES_NEW.' What do you infer about its behavior?

21. Which of the following methods should be invoked by the container to get a bean back to its working state?

22. Which of the following services does an EJB Server/Container provides to EJB?

23. A heavy tool manufacturing company manages its business and production by using enterprise beans. A session bean named 'Status' is used to get the production status for the day. The following code gets the context:

Context initialContext = new InitialContext();

The bean provides a local client view. For the local home interface named 'StatusHome.' What should be the lookup?

24. Which of the following statements is correct with regard to 'poison' message?

25. An online shop employs a stateless session bean (named 'Eshop') to process the requests. 'Eshop' uses a declarative transaction management system. The following code is from the xml deployment descriptor file of the bean:

1.        <ejb-jar>
2.        <enterprise-beans>
3.         <session>
4.                <ejb-name>Eshop</ejb-name>
5.                <home>com.solution.EshopHome</home>
6.                <remote>com.solution.Eshop</remote>
7.                <local-home>com.solution.EshopLocalHome</local-home>
8.                <local>com.solution.EshopLocal</local>
9.                <ejb-class>com.solution.EshopBean</ejb-class>
10.
11.
12.         </session>
13.        </enterprise-beans>
14.        </ejb-jar>

The session and transaction attributes are to be coded in the lines numbered 10 and 11. Which of the following options should be used to make the bean work as expected?

26. How do Enterprise Java Beans access the database?

27. By interoperating via IIOP, an EJB can directly access:

28. What is the restriction that EJB specification imposes on CMP fields?

29. The interface that must be implemented by a stateless session bean is javax.ejb.SessionBean.

30. Which of the following is a language in which IDL compiler of CORBA generates proxies and skeletons?

31. You define an enterprise bean as follows:

Public class CalcSessionBean implements javax.ejb.SessionBean

Which of the following method definitions is not mandatory?

32. The PrimaryKey class is used to provide each entity bean with a ____________:

33. Which of the following is a name of the design pattern not associated with EJB?

34. The methods declared in Session Bean interface are known as Callback (methods).

35. What will happen to the running session beans if the EJB container crashes or restarts?

36. The method ejbCreate() allows session beans to perform initializations. Which of the following methods should be called by the container before ejbCreate()?

37. An online medical shop uses Container Managed persistent beans for its operations. An OrderBean uses a query to list all the orders where payable amount is more than $800. The XML query tag in the deployment descriptor is as follows:

1. <query>
2.   <query-method>
3.         <method-name>findBigOrders</method-name>
4.        <method-params></method-params>
5.   </query-method>
6.
7. </query>

If the name of the table is 'Order' and total amount payable is in the column named 'amount,' which of the following queries can be placed in line 6?

38. A client wants to access Enterprise Java Bean for some processing. The first step will be looking up the class that implements its home interface. Which of the following should be used for the purpose?

39. The principal finder method that must be implemented by every entity bean class is:

40. Which of the following statements is incorrect with regard to the process of Instance Pooling in EJB?

41. We are saving a handle to an EJBObject named 'bookEJBObject' for an online book shop:

1. javax.ejb.Handle bookHandle = _____________;
2.
3. ObjectOutputStream stream =
4.                 new ObjectOutputStream(new FileOutputStream(fileName));
5.
6. stream.writeObject(bookHandle);
7. stream.close();

Which of the following methods should be filled in the blank?

42. A pre-cached instance is used to load state information on creation of an EJB.

43. Which of the following must be implemented by a JMS message-driven bean?

44. Which of the following statements are correct with regard to EJB QL?

45. Which of the following statements is correct with regard to the method ejbSelect()?

46. ______ bean supports asynchronous execution.

47. EJB's remote interfaces are split into what two groups?

48. Are CMTs active, or passive?

49. _____ is a model that enables beans to be saved in an XML format.

50. How many clients can access a stateless session bean?

51. The listener type of an event must be a descendent of _______.

52. True or False? EJB technology allows users to isolate their business logic away from the data layer by storing with the presentation layer.

53. _______ is not true of customizers.

54. What is EJB's transaction processing responsible for?

55. What happens if concurrent access is attempted on a single bean?

56. The ______ is an abstract representation of the container system to access a bean through methods that manage actions of the bean.

57. True or False? When an Application Exception occurs, the ejb container intercepts the exception, rolls back the transaction, and starts the clean up tasks.

58. A ______ property notifies listeners when its value changes.

59. When you create a combination of read-only and read-write EJBs, what pattern are you creating?

60. Are class methods declared by the Home interface tied to a specific instance?

61. ______ is an advantage of a session bean over an entity bean.

62. True or False? Enterprise Java bean is a form of Java bean.

63. Use the ______ interface when you need complete control over your bean's serialization.

64. True or False? Client code can access local beans.

65. A ______ property consults listeners before making a change and any one of the listeners may veto the change.

66. A ______ class for a bean changes how a bean appears in the builder tool by telling which properties should be listed first or which should be hidden.

67. If a bean is handling transactions via JTA API, what is happening?

68. When is it ideal to use a singleton session bean?

69. What two security mechanisms does EJB primarily use?

70. True or False? Any public method that is not part of a property definition is a bean method.

71. True or False? A boolean property in a bean class must have a public get method.

72. _____ is not an EJB interface.

73. What is responsible for the user interface logic on a client machine?

74. Can underlying table schemas be changed automatically by your EJB container?

75. True or False? For the class to be serializable, you must implement the Serializable interface in your class even if it is already implemented in a superclass.

76. Which of the following is a JNDI scope?

77. _______ provides a means for modifying the appearance and behavior of a bean within an application builder so it meets your specific needs.

78. _______ class does not support serialization.

79. What three files are used to control WebLogic Server EJB?

80. Object _____ means converting an object into a data stream and writing it to storage.

81. What is an example of a stateful session bean process?

82. What happens if two calling clients attempt to access a single bean?

83. What kind of programming does Java Message Service provide for EJB?

84. What has replaced the deployment descriptor in the newest version of EJB, 3.0?

85. How are EJB's two interfaces referred to?

86. _____ is NOT a method of the EntityBean Interface.

87. A ____ tag is used to represent an instance of a class in an XML bean archive.

88. True or False? A bean class can fire off any type of event except custom events.

89. True or False? The properties of a bean affect its appearance or internal state.

90. What is the javax.ejb.spi package used for?

91. How are stateless session beans different than stateful session beans?

92. ______ beans represent persistent data storage.

93. Beans are distributed as ____ files.

94. True or False? EJB is a client-side model that encapsulates the business logic of an application.

95. What is asynchronous pattern?

96. What is the EJB container responsible for assigning?

97. _____ bean stores data for a particular user for a single session.

98. Do clients of EJB instantiate beans directly?

99. A bean _______ is the code responsible for managing beans and the various interfaces.

100. A class is serializable if a class's inheritance hierarchy implements _________.