CP1 Tutorial 4

Question 1

Which of the following is the correct way to declare a variable of type int in Java?

Accepted Answer

int number;

Question 2

Which of the following is used to define a method in Java?

Accepted Answer

void method()

Question 3

Out of these two words; Rover and Pet, which one of these would be used for a class?

Accepted Answer

Pet

Question 4

What are the different type of visibility modifiers we can use in Java?

Accepted Answer

public, private, protected

Question 5

Which of the following is true about if statements in Java?

Accepted Answer

They execute a block of code only if a condition is true

Question 6

Which of the following is true about a String in Java?

Accepted Answer

A String is a sequence of characters

Question 7

What is the purpose of a constructor in Java?

Accepted Answer

To initialise an object and run code immediately after it is created

Question 8

Which of these is NOT a Java keyword?

Accepted Answer

function

Question 9

What is the purpose of a method in Java?

Accepted Answer

To define a block of code that performs a specific task when called

Question 10

Which of the following would you use to compare two strings for equality in Java?

Accepted Answer

.equals()

Question 11

Out of these two words; Christmas and Holiday, which one of these would be used for a class?

Accepted Answer

Holiday

Question 12

Which of the following is used to declare a class in Java?

Accepted Answer

class MyClass { }

Question 13

What is meant by the term visibility modifier?

Accepted Answer

A keyword that controls the accessibility of classes, methods and variables

Question 14

Which of the following methods is used to find the length of a String in Java?

Accepted Answer

length()

Question 15

If you had a class called Meeting, which operations would be defined in this class? (More than one answer)

Accepted Answer

sendInvitation, addAttendee, scheduleMeeting

Question 16

What are static variables?

Accepted Answer

Variables shared by all instances of a class

Question 17

Out of these two words; Superhero and Superman, which one of these would be used as an object?

Accepted Answer

Superman

Question 18

What class would the following snippet of code likely be from: return generator.nextInt(100) + 1;

Accepted Answer

RandomNumberGenerator

Question 19

What are instance variables?

Accepted Answer

Variables that store an object's state

Question 20

What is abstraction?

Accepted Answer

Hiding the irrelevant details and showing only the essential features

Question 21

Out of these two words; Justin and Person, which one of these would be used for a class?

Accepted Answer

Person

Question 22

If you had a class called Meeting, which attributes would be defined in this class? (More than one answer)

Accepted Answer

Attendees, Time, Date

Question 23

If you had a class called PictureFrame, which operations would be defined in this class? (More than one answer)

Accepted Answer

setHeight, getHeight, setWidth

Question 24

If you had a class called Topic, which operations would be defined in this class? (More than one answer)

Accepted Answer

setCategory, getTitle, addAuthor

Question 25

Out of these two words; Magazine and Time, which one of these would be used for a class?

Accepted Answer

Magazine

Question 26

Which of the following lines of codes are correct for assigning an age to a dog in the Dog class? (More than one answer)

Accepted Answer

d1.age = 4;, Dog d1 = new Dog("Spot", 4);, Dog d1 = new Dog("Spot"); d1.setAge(4);, d1.setAge(4);

Question 27

What roles do visibility modifiers play?

Accepted Answer

They control access to classes, methods, and variables

Question 28

Which symbols are used to create a comment in Java? (More than one answer)

Accepted Answer

/* */, //

Question 29

What is the name of the method used to start a Java program?

Accepted Answer

main()

Question 30

Which method is used to convert a String to an integer in Java?

Accepted Answer

Integer.parseInt()

Question 31

What are formal parameters?

Accepted Answer

Variables in a method declaration that accept values

Question 32

What is the purpose of a declaration in Java?

Accepted Answer

To allocate memory for variables and define their type

Question 33

Which of the following data types in Java is used to store a single character?

Accepted Answer

char

Question 34

What are actual parameters?

Accepted Answer

The values passed to a method when it is called

Question 35

How does a constructor differ from a method?

Accepted Answer

A constructor initialises an object, while a method performs an action

Question 36

What is encapsulation?

Accepted Answer

Hiding the details of how an object works and only showing what it can do

Question 37

What does public static void main(String[] args) represent in a Java program?

Accepted Answer

The main method that starts the program

Question 38

Out of these two words; Superhero and Superman, which one of these would be used for a class?

Accepted Answer

Superhero

Question 39

What class would the following snippet of code likely be from: System.out.println("The itsy bitsy spider");

Accepted Answer

Lyrics

Question 40

If you had a class called PictureFrame, which attributes would be defined in this class? (More than one answer)

Accepted Answer

Weight, Height

Question 41

Why is encapsulation important?

Accepted Answer

It protects an object's data and prevents unauthorised access

Question 42

Out of these two words; Magazine and Time, which one of these would be used as an object?

Accepted Answer

Time

Question 43

What are local variables?

Accepted Answer

Variables declared inside a method and accessible only within that method

Question 44

Out of these two words; Christmas and Holiday, which one of these would be used for a class?

Accepted Answer

Christmas

Question 45

Out of these two words; Justin and Person, which one of these would be used as an object?

Accepted Answer

Justin

Question 46

What is the purpose of a Scanner in Java?

Accepted Answer

To read user input

Question 47

Which of the following lines of codes are correct for updating a dogs weight in the Dog class? (More than one answer)

Accepted Answer

d1.setWeight(25);, Dog d1 = new Dog("Spot", 4, 20); d1.setWeight(25);

Question 48

How many constructors can there be for a single class?

Accepted Answer

A class can have any number of constructors

Question 49

Which of the following data types can store whole numbers in Java?

Accepted Answer

int

Question 50

Which method is used to convert a String to lowercase in Java?

Accepted Answer

toLowerCase()

Question 51

What does the == operator do in Java?

Accepted Answer

Checks whether two objects are pointing to the same memory location

Question 52

If you had a class called Topic, which attributes would be defined in this class? (More than one answer)

Accepted Answer

numUnits, topicName

Question 53

Why is abstraction important?

Accepted Answer

It simplifies complex systems by focusing on essential features

Question 54

Are constructors mandatory in class definitions?

Accepted Answer

No, if no constructor is provided, Java provides a default constructor

Question 55

Out of these two words; Rover and Pet, which one of these would be used as an object?

Accepted Answer

Rover

Question 56

Which of the following lines of codes are correct for assigning a name to a dog in the Dog class? (More than one answer)

Accepted Answer

Dog d1 = new Dog(); d1.setName("Spot");, d1.setName("Spot");

Question 57

What is the value of an int variable if it is declared but not initialised in Java?

Accepted Answer

0

Question 58

What is the difference between actual parameters and formal parameters?

Accepted Answer

Actual parameters are values passed, formal parameters are variables

CP1 Tutorial 4

Questions 58

CP1 Tutorial 4

Questions 58