Arraylist Q2

Question 1

Which of the following is NOT a method of the ArrayList class?

A.)delete()
B.)add()
C.)remove()
D.)clear()

Answer 1

A.)delete()

Question 2

2. What will the following code print? ArrayList cars = new ArrayList(); cars.add(‘RAIZE’); System.out.println(cars);

A.)Error
B.)[RAIZE]
C.RAIZE
D.)Π

Answer 2

B.)[RAIZE]

Question 3

3. What method is used to sort an ArrayList?

A.)organize()
B.)sort()
C.)order()
D.)arrange()

Answer 3

B.)sort()

Question 4

Which of the following is true about ArrayList elements?

A.)They can only be primitive types.
B.)They can be of any object type.
C.)They must be of the same type.
D.)They cannot be null.

Answer 4

B.)They can be of any object type

Question 5

Which method clears all elements from an ArrayList?

A.)empty()
B.)deleteAll()
C.)clear()
D )removeAll()

Answer 5

C.)clear()

Question 6

Which method is used to add an element to an ArrayList?

A.)append()
B.)add()
C.)insert()
D.)push()

Answer 6

B.)add()

Question 7

Which method would you use to remove an element from an ArrayList?

A.)erase()
B.)discard()
C.)remove()
D.)delete()

Answer 7

c.)remove()

Question 8

What is the correct way to loop through an ArrayList?

A.)for (int i = 0; i < list.length; i++)
B.)for (String item: list)
C.)for (int i: list)
D.)for (item in list)

Answer 8

B.)for (String item: list)

Question 9

What is the output of the following code?

ArrayList cars = new ArrayList(); cars.add(‘BMW’);
cars.add(‘Ford’); cars.remove(0);
System.out.println(cars);

A.)[]
B.)[BMW]
C.)[Ford]
D.)[Ford, BMW]

Answer 9

C.)[Ford]

Question 10

What does the size() method return?

A.)The type of elements in the ArrayList.
B.)The index of the last element.
C.)The maximum capacity of the ArrayList.
D.)The number of elements in the ArrayList.

Answer 10

D.)The number of elements in the ArrayList.

Question 11

How do you modify an element in an ArrayList?

A.)edit()
B.)change()
C.)set()
D.)update()

Answer 11

C.)set()

Question 12

How do you access the first element of an ArrayList named ‘cars’?

A.) cars[0]
B.) cars.get(1)
C.) cars.get(0)
D.) cars.first()

Answer 12

C.) cars.get(0)

Question 13

Which of the following is a valid way to create an ArrayList of integers?

ArrayList numbers = new
ArrayList();
ArrayList numbers = new
ArrayList();
ArrayList numbers = new
ArrayList();
ArrayList numbers = new
ArrayList();

Question 14

What is the main difference between a built-in array and an ArrayList in Java?

A.) Arrays can store objects only.
B.) ArrayLists can be resized dynamically.
C.) Arrays can be resized dynamically.
D.) ArrayLists can only store strings.

Answer 14

B.) ArrayLists can be resized dynamically.