Deck 11: Multiple Classes and Inheritance

Question 1

The code in a constructor procedure executes after any other code in the object._________________________

Answer 1

False,before

Question 2

To use a three-tier structure for a program,you must divide the processing into ____.

A) baselines
B) indices
C) classes
D) references

Answer 2

C

Question 3

____ is a major contributor to reliable and robust programs.

A) Resolution
B) Concatenation
C) Encapsulation
D) Identification

Answer 3

C

Question 4

In a three-tier architecture,the business tier contains the ____ that must occur to fulfill the requirements of the program.

A) logic
B) objects
C) syntax
D) calculations

Question 5

The SelectedIndex property of a ComboBox object will contain the value ____ if a selection has been made.

A) -1
B) 0
C) of the entry
D) True

Question 6

The WriteLine procedure will ____.

A) write a record to a file
B) place a line return in the file
C) update an existing record in a file
D) close a StreamWriter

Question 7

The ____ property should be tested to ensure that a masked textbox contains characters for the entire mask area.

A) MaskRange
B) MaskFull
C) MaskComplete
D) CompleteMask

Question 8

In a three-tier architecture,only the presentation tier will actually read and write data._________________________

Question 9

Concatenation is a major contributor to reliable and robust programs._________________________

Question 10

Inheritance allows one class to gain ____ from another class.

A) attributes
B) records
C) procedures
D) bases

Question 11

Use the ____ function to test an input value to ensure that it is numeric.

A) IsNumber
B) IsNumeric
C) TestNumber
D) TestNumeric

Question 12

In a three-tier architecture,only the persistence classes will actually ____ data.

A) record
B) read
C) index
D) write

Question 13

The TabIndex property determines which object on a form receives the focus when the user presses the ____ key.

A) ALT
B) SPACEBAR
C) TAB
D) BACKSPACE

Question 14

A subclass is always in a "has-a" relationship with the base class._________________________

Question 15

The MaskFull property will return a value of ____ if the mask area of a masked textbox is not completely filled.

A) True
B) False
C) 0
D) -1

Question 16

To specify the sequence of objects (like those in the accompanying figure)that will be selected when the TAB key is pressed,the ____ property is used.

A) TabIndex
B) TabOrder
C) SelectedIndex
D) SelectedItem

Question 17

In a ComboBox object,the SelectedIndex property will contain a value of ____ if no selection has been made.

A) -1
B) 0
C) 1
D) null

Question 18

In a three-tier architecture,the ____ tier contains the classes that display information and accept user input.

A) validation
B) presentation
C) business
D) persistence

Question 19

Data access tier is another name for the presentation tier._________________________

Question 20

The ____ tier is a tier within the three-tier structure into which programs are divided.

A) Presentation
B) Records
C) Business
D) Persistence

Question 21

In a three-tier architecture for Web applications,the ____ tier contains the Web page that appears to the user.

A) business
B) interface
C) persistence
D) presentation

Question 22

Data that is ____ remains after the program is terminated.

A) extant
B) legacy
C) lingering
D) persistent

Question 23

The ____ tier implements the "business rules" required for the application.

A) business
B) data access
C) data processing
D) rules

Question 24

The processing in the ____ tier ensures that valid data is entered into the program for processing in the business tier.

A) validation
B) presentation
C) business
D) persistence

Question 25

Whenever inheritance is used,the subclass must fit into a(n)____ relationship with the base class.

A) equivalence
B) "has-a"
C) helper
D) "is-a"

Question 26

A subclass inherits attributes from a(n)____ class.

A) inheriting
B) disseminating
C) distributing
D) base

Question 27

In a three-tier architecture,the ____ tier contains the logic and calculations.

A) business
B) persistence
C) presentation
D) validation

Question 28

The ____ prepares an object for use in the program.

A) constructor
B) class variable
C) class declaration
D) destructor

Question 29

____ is the concept of separating processing and hiding data within specific classes.

A) Encapsulation
B) Inheritance
C) Object-oriented programming
D) Persistence

Question 30

Data that is stored in a file or database on disk often is called ____ data.

A) persistent
B) extant
C) resistant
D) existing

Question 31

The ____ keyword is used to declare a variable that will contain the address of an object created from a class.

A) Dec
B) Const
C) Dim
D) Set

Question 32

Which of the following contains the correct code to create and instantiate an object named MyStudent from a class named Student?

A) Dim objStudent As Student
B) Dim objStudent As New Student
C) Dim objStudent = Student
D) Dim objStudent = New Student

Question 33

When designing a program using the three-tier approach,a primary rule is that classes in the presentation tier can communicate only with classes in the ____ tier.

A) business
B) data access
C) persistence
D) validation

Question 34

If the developer writes no code for a class ____,Visual Basic automatically generates any processing that must be accomplished to prepare the object for use.

A) builder
B) constructor
C) creator
D) instantiator

Question 35

The code in a(n)____ procedure executes before any other code in an object.

A) beginner
B) builder
C) constructor
D) instantiation

Question 36

When an object requires data when it is instantiated,the data can be passed as part of the ____ code.

A) encapsulation
B) inheritance
C) instantiation
D) declaration

Question 37

When a class is ____ into an object using the New keyword,a special procedure called a constructor is executed in the class.

A) encapsulated
B) inherited
C) instantiated
D) constructed

Question 38

The ____ tier is also called the data access tier in a three-tier architecture.

A) presentation
B) business
C) persistence
D) data processing

Question 39

The ____ statement can be used to instantiate an object from a class.

A) Create
B) CreateObject
C) Instantiate
D) New

Question 40

In a three-tier architecture,the classes in the ____ tier generally use data entered by users and data obtained from storage.

A) processing
B) persistence
C) presentation
D) business

Question 41

Validation of user input data should occur in the business tier of a three-tier architecture.

Question 42

The presentation tier of the three-tier structure consists of one or more forms and the objects placed on the forms.

Question 43

In a three-tier architecture,the business classes should not be concerned with the functionality of the user interface.

Question 44

A new class can be added to an application by pressing and holding,or right-clicking,the project name in the Solution Explorer window.

Question 45

In a three-tier architecture,user interface classes should not be concerned with how the data is manipulated by the business classes.

Question 46

To ensure that variables declared in a base class may be accessed by its subclasses but not by other classes,the variables should be declared with ____ access.

A) Private
B) Protected
C) Public
D) Restricted

Question 47

A ____ text file can be read into programs such as Microsoft Excel and Microsoft Access to import the data into the application.

A) comma-delimited
B) case
C) streamed
D) delimiter written

Question 48

The business tier of a three-tier architecture contains the code required to read and write data from permanent storage.

Question 49

Which tier is involved in saving data stored on a USB drive?

A) persistence
B) business
C) override
D) constructed

Question 50

____ the text means writing the next record in the file following the last record currently in the file.

A) Integrating
B) Coding
C) Executing
D) Appending

Question 51

In a three-tier architecture for a Web application,the Web form and Web page constitute the persistence tier.

Question 52

A constructor procedure is identified by the keyword ____.

A) Con
B) Create
C) Constr
D) New

Question 53

A procedure in a subclass that has the same name as a procedure in its base class must be declared in the subclass with the ____ keyword.

A) Overridable
B) Overrides
C) Replaceable
D) Replaces

Question 54

Both a base class and its subclass must have ____.

A) constructors
B) objects
C) libraries
D) glossaries

Question 55

In a three-tier architecture,the user interface classes should have nothing to do with how data is validated.

Question 56

When using inheritance,the class that provides attributes to be inherited is called the ____ class.

A) inheriting
B) base
C) distributing
D) disseminating

Question 57

A class that inherits attributes from another class is called a(n)____.

A) ascendant
B) base class
C) inheritor
D) subclass

Question 58

An object acts as a template for a class.

Question 59

A class can only be used in one program for one purpose.

Question 60

A comma separates each field in a record in a comma-____ file.

A) persistent
B) tiered
C) delimited
D) based

Question 61

The Visual Basic statement "Dim objStudent As Student"will create and instantiate an object.

Question 62

Statements outside a base class and its subclasses can reference variables declared in the base class with Protected access.

Question 63

The ____________________ tier consists of one or more forms like the one in the accompanying figure.

Question 64

Data cannot be passed into an object when it is being instantiated.

Question 65

To determine if a selection was made in a combo box,the value of the ____________________ property should be tested.

Question 66

The ____________________ property identifies if all digits have been entered into the mask.

Question 67

The TabIndex property of objects on a Windows form controls the order that objects will be selected when the user presses the ____________________ key.

Question 68

To call a procedure in another object,a statement in the calling object must identify both the object and the procedure within the object.

Question 69

The ____________________ property is used to specify the sequence of objects on a Windows form that will be selected when the Tab key is pressed.

Question 70

Generally,when using multiple classes within a program,variables in a class should not be available to code within other classes within the program.

Question 71

You must instantiate an object based on a class in order for the processing in the object to take place.

Question 72

When using inheritance,a subclass can use variables within its base class.

Question 73

If the developer writes no code for a class constructor,Visual Basic automatically generates whatever processing must be accomplished to prepare the object for use.

Question 74

When a subclass is instantiated,only the subclass's constructor is executed.

Question 75

When arguments are passed ByVal,it means the original value is passed to the instantiated object and a copy of the value is not used.

Question 76

A constructor procedure cannot contain arguments.

Question 77

A procedure in one class cannot call a procedure in another class within the program.

Question 78

An outside class cannot call an overridable procedure in the subclass.

Question 79

When using inheritance,a subclass cannot use the procedures within the base class.

Question 80

The subclass can use attributes from the base class as if those attributes were defined in the subclass.