java programming : In this exercise, you will design various classes and write a program to computerize the billing system of a hospital. 13. Design

java programming : In this exercise, you will design various classes and write a program to
computerize the billing system of a hospital.
13.
Design the class Doctor, inherited from the class Person, defined
in Chapter 8, with an additional data member to store a doctor’s
specialty. Add appropriate constructors and methods to initialize, access,
and manipulate the data members.
a.
b. Design the class Bill with data members to store a patient’s ID and
the patient’s hospital charges such as pharmacy charges for medicine,
the doctor’s fee, and the room charges. Add appropriate constructors
and methods to initialize, access, and manipulate the data members.
Design the class Patient, inherited from the class Person, defined in
Chapter 8, with additional data members to store a patient’s ID, age, date of
birth, attendingphysician’s name, the date when the patient was admitted in the
hospital, and the date when the patient was discharged from the hospital. (Use
the class Date to store the date of birth, admit date, discharge date, and the
class Doctor to store the attending physician’s name.) Add appropriate
constructors andmethods to initialize, access, and manipulate the data members.
Write a program to test your classes.