Problem:

Question: Declare a class called Quadrilateral that can be used to represent a quadrilateral.

What instance variables are required?

This class should include the following methods:

• Accessor and mutator methods. Notice that negative and zero lengths should not be accepted.
• A method called isParallelogram that returns a Boolean value indicating if the quadrilateral is a parallelogram.
• A method called isRectangle that indicates if the quadrilateral is a rectangle. This method should invoke the method isParallelogram and return a Boolean value.
• A method called isSquare that returns the Boolean value "true" if the quadrilateral is a square. This method should invoke the method is Rectangle and return a Boolean value.

Implement the class and write a program to test its methods and submit your source code (.java files).

Write the code step by step and explain it.