polymorphism in C++

[logistic_guy]

Modify the payroll system of Figs. $\displaystyle 12.9–12.17$ to include private data member $\displaystyle \text{birthDate}$ in class $\displaystyle \text{Employee}$. Use class $\displaystyle \text{Date}$ from Figs. $\displaystyle 10.6–10.7$ to represent an employee’s birthday. Assume that payroll is processed once per month. Create a vector of Employee references to store the various employee objects. In a loop, calculate the payroll for each Employee (polymorphically), and add a $\displaystyle \$ 100.00$ bonus to the person’s payroll amount if the current month is the month in which the Employee’s birthday occurs.

 

[khansaheb]

Modify the payroll system of Figs. $\displaystyle 12.9–12.17$ to include private data member $\displaystyle \text{birthDate}$ in class $\displaystyle \text{Employee}$. Use class $\displaystyle \text{Date}$ from Figs. $\displaystyle 10.6–10.7$ to represent an employee’s birthday. Assume that payroll is processed once per month. Create a vector of Employee references to store the various employee objects. In a loop, calculate the payroll for each Employee (polymorphically), and add a $\displaystyle \$ 100.00$ bonus to the person’s payroll amount if the current month is the month in which the Employee’s birthday occurs.

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

READ BEFORE POSTING​

Please share your work/thoughts about this problem

 

[logistic_guy]

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:

READ BEFORE POSTING​

Please share your work/thoughts about this problem

I respect you khan, but I doubt it you understand polymorphism!

 

[khansaheb]

I respect you khan, but I doubt it you understand polymorphism!

My understanding is NOT required here. What is required is every student that asks question here IS required to explain - "where they are stuck".
Nobody touched this problem for 15 days - because you failed to provide a point "to start".

I am an Engineer - I do not understand polymorphism - I did not ever use it in any shape or form. However, my wife is a computer scientist with Degrees from University. So I had a walking reference - other than using AI.

 

[logistic_guy]

My understanding is NOT required here. What is required is every student that asks question here IS required to explain - "where they are stuck".
Nobody touched this problem for 15 days - because you failed to provide a point "to start".

I am an Engineer - I do not understand polymorphism - I did not ever use it in any shape or form. However, my wife is a computer scientist with Degrees from University. So I had a walking reference - other than using AI.

I knew that you don't understand polymorphism and I also know that no one in this site understands polymorphism. I understand polymorphism, so it's either @Ted promotes me to a moderator, or this site will lack the ability to help all types of students.

I will dedicate some of my time to help students understand how to solve problems involving polymorphism. I will teach them the art of polymorphism.

Professor khan, you were so lucky when you entered this thread because soon you will understand some of the ideas behind polymorphism. Just make sure that you come back to this thread from time to time!

 

[khansaheb]

you will understand some of the ideas behind polymorphism

My cup runneth over - I do not need to understand polymorphism in CS. Like I said - I am surrounded by experts in CS.

Now polymorphism in material (crystals) - there lies my expertise......

 

[logistic_guy]

My cup runneth over - I do not need to understand polymorphism in CS. Like I said - I am surrounded by experts in CS.

Then, you'll be missing the joy of your half-life.

 

[logistic_guy]

In this game of polymorphism, we will create $\displaystyle 5$ classes.

$\displaystyle \bold{1.} \ \text{Employee}$
$\displaystyle \bold{2.} \ \text{SalariedEmployee}$
$\displaystyle \bold{3.} \ \text{CommissionEmployee}$
$\displaystyle \bold{4.} \ \text{BasePlusCommissionEmployee}$
$\displaystyle \bold{5.} \ \text{Test}$

 

[logistic_guy]

In this game of polymorphism, we will create $\displaystyle 5$ classes.

$\displaystyle \bold{1.} \ \text{Employee}$
$\displaystyle \bold{2.} \ \text{SalariedEmployee}$
$\displaystyle \bold{3.} \ \text{CommissionEmployee}$
$\displaystyle \bold{4.} \ \text{BasePlusCommissionEmployee}$
$\displaystyle \bold{5.} \ \text{Test}$

Each class will have $\displaystyle 2$ files. A header file and a source file.

For example,

$\displaystyle \text{Employee}$.h
$\displaystyle \text{Employee}$.cpp

 

[logistic_guy]

Each class will have $\displaystyle 2$ files. A header file and a source file.

Except the $\displaystyle \text{Test}$ class, it will only have one file $\displaystyle \rightarrow$ a source file where the main function lives there.

Every C++ program has a main function and now we know where is that bastard.

 

[logistic_guy]

Here is the deal (hierarchy).

The $\displaystyle \text{Employee}$ class is the boss $\displaystyle \rightarrow$ it is the base class.

The $\displaystyle \text{SalariedEmployee}$ and $\displaystyle \text{CommissionEmployee}$ classes inherit the properties of the $\displaystyle \text{Employee}$ class $\displaystyle \rightarrow$ they are derived classes.

The $\displaystyle \text{BasePlusCommissionEmployee}$ class inherits the properties of the $\displaystyle \text{CommissionEmployee}$ class $\displaystyle \rightarrow$ it is also a derived class but from the $\displaystyle \text{CommissionEmployee}$ class.

The $\displaystyle \text{Test}$ class is the fun boy $\displaystyle \rightarrow$ it collects all information or data from other classes and manipulate their behavior. It is capable to manipulate their behavior normally or polymorphically. The later is the concept of this game!

 

[logistic_guy]

Let us assume that the payroll system works perfectly polymorphically with those $\displaystyle 5$ classes. Now we want to add a data member $\displaystyle \text{birthDate}$ of type $\displaystyle \text{Date}$ in $\displaystyle \text{Employee}$ class.

We have already seen before how $\displaystyle \text{Date}$ class works. So, we don't need to explain it again.

Let us write the first file $\displaystyle \rightarrow \ \text{Employee}$.h

include $\displaystyle \text{Date}$.h
include string

class $\displaystyle \text{Employee}$ starts
public:
$\displaystyle \text{Employee}$(const std::string&)
virtual ~$\displaystyle \text{Employee} \ =$ default

void setFirstName(const std::string&)
std::string getFirstName() const

virtual std::string toString() const

private:
std::string firstName
Date birthDate
ends



This header file includes:

Five prototypes.
constructor
destructor
$\displaystyle 3$ data member functions

It also includes $\displaystyle 2$ data members $\displaystyle \rightarrow 2$ variables

 

[logistic_guy]

We are writing the source file $\displaystyle \rightarrow \text{Employee}$.cpp
include sstream
include $\displaystyle \text{Employee}$.h
using namespace std

Employee::$\displaystyle \text{Employee}$(const string& first, unsigned int m, unsigned int d, unsigned int y)
: firstName(first), birthDay($\displaystyle \text{Date}$(m,d,y))

void Employee::setFirstName(const string& first)
firstName = first

string Employee::getFirstName() const
return firstName

string Employee::toString() const
return getFirstName()