Java Quiz 2- Classes, Collections, Threads

Which of the following is a correct definition of a class?

• a) An instance of an object

• b) A blueprint or prototype for creating objects

• c)A method in Java

• d) A package in Java

Which keyword is used to refer to the current instance of an object within a class?

• a) object

• b) this

• c) self

• d) class

Which of these best describes "Encapsulation"?

• a) Breaking a complex problem into simpler pieces

• b) Inheriting properties from a parent class

• c) Implementing multiple interfaces

• d) Wrapping up of data and methods into a single unit

Can a class have multiple constructors?

• Yes

• No

Which keyword is used to implement an interface?

• a) extends

• b) new

• c) interface

• d) implements

How many interfaces can a Java class implement?

• a) None

• b) Only one

• c) Two

• d) As many as needed

An interface with no methods is known as?

Which of these can be contained in an interface?

• a) Abstract methods

• b) Constants

• c) Default and static methods

• d) All of the above

What is the default access modifier of a method in an interface in Java?

• a) private

• b) public

• c) protected

• d) None of the above

Which of the following is a part of the Java Collections Framework?

• a) ArrayList

• b) Array

• c) int[]

• d) String