Activity 7: Quiz

Which of these class is super class of every class in Java?

• String class

• Object class

• ArrayList class

• Abstract class

Which of these keywords can be used to prevent inheritance of a class?

• super

• constant

• extends

• final

Which of these class relies upon its subclasses for complete implementation of its methods?

• Object class

• abstract class

• ArrayList class

• None of the mentioned

What will be the output of the following Java program?

• 2

• 0

• Compilation Error

• Runtime Error

Which of these keywords are used to define an abstract class?

• Abstract

• abstract

• abstract class

• abst

What is not type of inheritance?

• Single inheritance

• Double inheritance

• Hierarchical inheritance

• Multilevel inheritance

In order to restrict a variable of a class from inheriting to subclass, how variable should be declared?

• Protected

• Private

• Public

• Static

If super class and subclass have same variable name, which keyword should be used to use super class?

• this

• super

• upperclass

• classname

What is the use of final keyword in Java?

• When a class is made final, a sublcass of it can not be created.

• When a method is final, it can not be overridden.

• When a variable is final, it can be assigned value only once.

• All of the above

Which is the opposite of an Abstract Class?

• Interface

• concrete class

• none of the above

• all the above