Classes and Objects?

[KaraPardue]

How would I create a .cpp file that calls all of the functions.
Here is my header file:

// This is the inventory.h file.
// It contains the Inventory class declaration.

#ifndef INVENTORY_H
#define INVENTORY_H

class Inventory
{
private:
	int itemNumber;
	int quantity;
	double cost;
	double totalCost;
public:
	// Default constructor
	Inventory()
		{ itemNumber = quantity = cost = totalCost = 0; }
	
	// Overloaded constructor
	Inventory(int, int, double);	// Defined in Inventory.cpp

	// Mutators (i.e., "set" functions) defined in Inventory.cpp
	void setItemNumber(int);
	void setQuantity(int);
	void setCost(double);

	// setTotalCost calculates the total cost
	// and stores the result in the totalCost member
	void setTotalCost()
		{ totalCost = cost * quantity; }

	// Accessors (i.e., "get" functions)
	int getItemNumber()
		{ return itemNumber; }
	int getQuantity()
		{ return quantity; }
	double getCost()
		{ return cost; }
	double getTotalCost()
		{ return totalCost; }

	// Input validation functions
	bool validInt(int);
	bool validFloat(double);
};

#endif 

And here is my .cpp file.

// This is the inventory.cpp file.
// It contains the Inventory class function definitions. 

#include <iostream>
#include "Inventory.h"
using namespace std;

//************************************************************
// Overloaded constructor
// Accepts arguments to be stored in each member variable.
//************************************************************
Inventory::Inventory(int in, int q, double c)
{ 
	setItemNumber(in);
	setQuantity(q);
	setCost(c);
	setTotalCost();
}

//************************************************************
// setItemNumber accepts an argument to be stored in item number.
//************************************************************
void Inventory::setItemNumber(int in)
{
	while (!validInt(in))
	{
		cout << "Item Number must be positive. Please re-enter: ";
		cin  >> in;
	}
	itemNumber = in; 
}

//************************************************************
// setQuantity accepts an argument to be stored in quantity.
//************************************************************
void Inventory::setQuantity(int q)
{
	while (!validInt(q))
	{
		cout << "Quantity must be positive. Please re-enter: ";
		cin  >> q;
	}
	quantity = q; 
}

//************************************************************
// setCost accepts an argument to be stored in cost.
//************************************************************
void Inventory::setCost(double c)
{
	while (!validInt(c))
	{
		cout << "Cost must be positive. Please re-enter: ";
		cin  >> c;
	}
	cost = c; 
}

//************************************************************
// The validInt member tests its integer argument to see 
// if it is negative. If the argument is negative, the function 
// returns false. Otherwise, the function returns true.
//************************************************************
bool Inventory::validInt(int value)
{
	if (value < 0)    // the value is negative so it is NOT valid
		return false;
	else              // the integer value is valid
		return true;  
}

//************************************************************
// The validFloat member tests its floating-point argument to see
// if it is negative. If the argument is negative, the function 
// returns false. Otherwise, the function returns true.
//************************************************************
bool Inventory::validFloat(double value)
{
	if (value < 0)    // the value is negative so it is NOT valid
		return false;
	else              // the floating-point value is valid
		return true;
}

Now I need to create another .cpp file to prove that the functions work, and I have to create one or more inventory objects to call all of the functions. I'm not quite sure how to go about this...All I have so far are the #include statements and i'm stuck. Can anyone help?

[DarioDigiuni]

1. Pls use the source code button
2. What do you mean with

to prove that the functions work

Do you need a test main for that?

[KaraPardue]

1. Sorry.
2. I need to call all of the functions.

and yes

[DarioDigiuni]

I don't see the problem. Why can't you just

0. #include <Inventory.h>
1. Instantiate an inventory object.
2. Call in sequence the set and get methods, cout-ing the results.

Or do you want to automatically generate the code? I don't think so, but in case you could use Boost.Preprocessor.

[KaraPardue]

I am just having problems writing the code for the set and get methods.

[Peter87]

If you set a value you should get the same value back from the get function (if it's a validInt).
You can make some tests in a loop and print an error if you get the wrong value.

I know it can feel strange to write unit tests for setters and getters because the code needed is more complicated than the code inside the functions and it's a greater chance you make a mistake in the test than in the real code, but I guess that's just how it is.

[KaraPardue]

Yeah...thanks!
I will try to do that.

[bluecoder]

[code]int Inventory::getItemNumber()
{
	return itemNumber ; 
}

//************************************************************

//************************************************************
int Inventory::getQuantity()
{
	return quantity ; 
}

//************************************************************

//************************************************************
int Inventory::getCost()
{
	return cos

t;
}
[/code]

[trailfrenzy]

The accessor methods should be constant i.e.

	// Accessors (i.e., "get" functions)
	int getItemNumber() const
		{ return itemNumber; }

[KaraPardue]

I cannot get that code to work...because it's not letting me use getItemNumber outside of it's class.

[DarioDigiuni]

Let me do your homework.

int main(int argc,char* argv[])
{
 Inventory inventory(1,2,3.0);

 std::cout << inventory.getItemNumber() << std::endl;
 std::cout << inventory.getQuantity() << std::endl;
 std::cout << inventory.getCost() << std::endl;

 inventory.setItemNumber();
 std::cout << inventory.getItemNumber() << std::endl;

 return 0;
}

And so on.