Exam 1

Question 1

Object-oriented programming (OOP) is popular because:

Answer 1

• it enables reuse of previous code saved as classes

- which saves time because previously written code has been tested and debugged already

Question 2

If a new class is similar to an existing class, the existing class can be:

Answer 2

Extended

Question 3

This extension of an existing class is called:

Answer 3

Inheritance

Question 4

Inheritance creates an is-a relationship, meaning the child is a more ___________________ of the parent.

Answer 4

Specific version

Question 5

//mammal

drinkMothersMilk()
^
|
thinkCreatively()

A human is a:

Human has all the data fields and methods defined by:

Human is a __________ of mammal

Human may define other variables and methods that ______ contained in mammal

Answer 5

Mammal

Mammal

Subclass

Are not

Question 6

The keyword ___________ creates an inheritance relationship

Answer 6

extends

Question 7

Only ______________ need to be declared

Answer 7

Additional data fields

Question 8

A notebook object contains the data fields declared in both the____________ and _____________ objects

Answer 8

Computer and notebook

Question 9

If data fields are declared as __________ in the superclass, they are not directly accessible in the subclass

Answer 9

Private

Question 10

If the execution of any constructor in a subclass does not invoke a superclass constructor—an explicit call to super()—java automatically invokes the __________________ for the superclass

Answer 10

No-parameter constructor

Question 11

If no constructors are defined for a class, the _________________ for that class is provided by default

Answer 11

No-parameter constructors

Question 12

If any _____________ are defined, you must explicitly define a no-parameter constructor

Answer 12

Constructor

Question 13

Variables with a private visiability cannot be accessed by a:

Answer 13

Subclass

Question 14

Variables with ___________ visibility are accessible by any subclass or any class in the same package

Answer 14

Protected

Question 15

In general, it is better to use ____________ visibility and to restrict access to variables to accessor methods

Answer 15

Private

Question 16

In an __________ or __________ relationship, one class is a subclass of the other class

Answer 16

is-a or inheritance

Question 17

In an __________ or __________ relationship, one class has the other class as an attribute

Answer 17

has-a or aggregation

Question 18

Methods in the class hierarchy which have the same name, return type, and parameters ___________ corresponding inherited methods

Answer 18

Override

Question 19

When overriding a method, the method must have the same ________ and the same _________ and types of ________ in the same order. Otherwise, the method will overload

Answer 19

Name
Number
Parameters

Question 20

It is good programming practice to use the __________ annotation in your code

Answer 20

@override

Question 21

Polymorphism means:

Answer 21

Having many shapes

Question 22

Polymorphism is a central feature of:

Answer 22

OOP

Question 23

Polymorphism enables the JVM to determine at run time which of the classes in a hierarchy is referenced by a _________________ or ____________

Answer 23

Superclass variable or parameter

Question 24

Why does polymorphism works because:

Answer 24

An object of a subclass can be used wherever an object of its superclass is expected

Question 25

Polymorphism _____________ programming when writing methods with class parameters

Answer 25

Simplifies

Question 26

What are the two parts of an ADT? Which part is accessible to a user and which is notExplain the relationships between an ADT and a class; between an ADT and an interface and berween an interface and classes that implement the interface.

Answer 26

of data elements and methods that data. user can access operations, but cannot the structure of the elementsA class ADT Ajava interface way to specify or ADT. A interface defines set of methods, and class that implements these and