In java

Make an Abstract class Employee with a name and monthly salary.

Make a class Manager Inherit from Employee. Add and instance variable,named department, of type String

Make a class Executive inherit from Manager

Make a regular class that inherits from Employee.

It should also include an abstract method calculateBonus() as shown below:

abstract public int calculateBonus();

According to the following rules:

A Managers bonus is calculated by multiplying his salary by 2.

An Executive's bonus is calculated by multiplying his salary by 3.

A Regualrs bonus remains unchanged.

Supply a test program that tests these classes and methods. Your test should also create objects of each type , add them to an ArrayList and use that ArrayList to demonstrate dynamic Polymorphism.