First C++ project e-commerce site

Object Oriented Programming Languages and Environments

First C++ project

You are to implement an e-commerce site for selling household appliances, such as dishwashers, laundry
machines, and clothes dryers. Your client is Ms. Rosey Sowpe, who owns an appliance shop. Your task
for this project is to implement a proof-of-concept prototype in C++11. Your prototype will manage the
appliances for sale in Ms. Sowpe’s site. Each appliance contains the following fields:
1. ID—This is a unique (integer) identifier for each appliance.
2. Type—The type of an appliance is an enumeration with possible values of LAUNDRY MACHINE,
DISH WASHER, and DRYER.
3. Manufacturer—This is a string denoting the company making the appliance (e.g., “Whirpool”).
4. Price—This is the price of the product in US dollars and cents.
5. Pictures—An array of file paths containing a list of pictures for each appliance in an appropriate
format (e.g., PNG, JPEG, etc.)
The last item above is an array of strings denoting file paths. Each file path identifies a file containing
a byte sequence meant to display a picture of an appliance on the user’s display. For the time being,
you do not have to worry about creating, storing or displaying the images; you may assume that this
functionality will be implemented by someone else. However, you must make provisions for the fact that
images will be relatively large, making each appliance instance expensive to store in memory.
To avoid cluttering the primary memory of your computer with images, you must store your appliance
instances in files most of the time. Each such file will contain information a single appliance instance
including its ID, Type, Manufacturer, etc. Also, you should implement a smart pointer class called
AppliancePtr that dynamically loads instances of class Appliance when they are needed and stores them
back on file when done with an appliance.
You are to code a test version of the program that contains just 10 appliances denoted by unique
IDs 0 through 9. Each of the ten instances is stored in a separate file. At any point in time, only three
of the appliance instances can be stored in memory; the remaining instances exist only in the ten files
associated with your project.
When the program is started, the program creates a linked list of 10 appliance pointers; however,
none of the appliance instances are loaded in memory. Next, appliances are loaded from memory and
stored back to files (possibly after being modified) as needed while executing the commands described
next. However, you should never hold more than 3 appliance instances in memory at all times.
Your project should support the command line interface below; no GUI is needed for this project.
Your command line interface will prompt the user for a command, and then execute the command. Here is
a list of commands. Make sure not to cause any memory leaks or dangling pointers in the implementation
of these commands.
1. l—List all appliances. Each appliance is loaded from disk and its information (ID, Type, etc.) is
displayed in the user’s screen, including the list of file paths, but with no images of the appliance.
Appliance instances are stored back on disk and deleted as needed to keep a maximum of three
total appliances in memory at all times.
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2. 0 . . . 9—Edit a appliance. This command sets the numbered appliance to be the current appliance.
If the appliance is not already in memory, it is loaded from disk and assigned to the corresponding
appliance pointer. In this case, an appliance instance currently in memory may have to be stored
back into its corresponding file and deleted from memory not to exceed the limit of 3 appliances.
3. c—Create an appliance. The user is prompted for the various fields in the appliance instance. The
appliance is then stored to a file and associated smart pointer instance. The appliance’s ID must
be between 0 and 9. If an appliance with the same ID existed before this appliance is created, the
older appliance is deleted from both memory and the associated file.
4. p—This command changes the price of the current appliance. The user is prompted for a new
number, which becomes the new price of the appliance. The current appliance is not saved to file
as part of this command. The new content of current appliance is displayed in the user’s screen.
The new price will be saved when the appliance instance is stored to its file.
5. s—Save all appliances. This command save the appliance(s) currently in memory to the corresponding file(s). First, the files are deleted (e.g., using the remove() function). Next, an ofstream instance
is opened on the named file, and the appliance’s information is saved to the new file. Finally, the
stream is closed.
6. q—Quits the appliance manager.
Implementation notes. Your appliance manager must meet the following requirements. First, each
appliance pointer should handle exactly one appliance. Second, clients (i.e., your project code) should
not be allowed to create or delete appliance instances directly; these functions are handled by the smart
pointer. Third, clients should not be allowed to duplicate (copy) smart pointers, or to switch the appliance
instance associated with a a given smart pointer instance. Fourth, the API of the AppliancePtr class
should include both operator*() and operator-(). Finally, you must code the linked list yourself, without
relying on classes defined, e.g., in the Standard Template Library (STL) or other libraries.
You must work alone on this project. Save all your code in a collection of header and code files
and submit a zip archive with a (short) readme file containing instructions on how to use your Appliance
Manager. The archive should also contain sample text files describing your initial appliances. Submit
the archive by clicking on the link provided with this assignment. Your code should compile under the
GNU C++11 compiler. No late submissions will be accepted.
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