CSc 331 - Spring 2018
Lab Exercise #5

Preparation

• Create a lab5 directory to organize your files (for you, and for electronic submission) Copy the java files from ~hohman/331/s18/labs/lab5 into your lab 5 directory.

Additional Information / Guidelines

• The Java Collections Framework is in the java.util package.
• Please follow the Java coding conventions: class names start with a capital letter and method names begin with a lower-case letter. Getters are named as getPrivateDataMember.
• All classes are public - and abstract as appropriate.
• All data members are private.
• Do not add unnecessary setters to you classes.
• Just one class per file.

Coding Suggestions

• My solution has exactly 1 setter.
• toString functions are very useful here. For examples, toString for a Product might return "Amazon Dot, Price $69.99". And toString for a CartItem might return "3 of Amazon Dot, Price $69.99"

Exercise 1:

Your task is to design and code this "shopping cart" prototype. Note that (for now) this prototype does not check the validity of input values. For example, it does not check for invalid pid's, invalid cart id's, etc.

Needless to say?? this version should be coded in the distributed "style" discussed in class.

Catalog: The Catalog for the OnlineStore contains a Map of the available Products. Here the key is the 3-digit product id.

OnlineStore: This class is intended to accept commands from some user interface - a web or some other GUI. It will be able to create and remove Carts from its Map of ShoppingCart's. Carts are identified by an int id number. The first cart created will be cart #1, the next will be cart #2, etc.
It should also have methods to

• addToCart(cartId, productId, quantity)
• removeFromCart(cartId, productId)
• updateQuantity(cartId, productId, newQuantity)
• viewCart(cartId)
  Note that viewCart does display the total number of items in the cart and a subtotal.
• checkOut(cartId)
  Note this checkOut will remove the shopping cart from the pool of carts, and calculate and display GST (5%), provincial sales tax (7%), add a $10 shipping charge if the subTotal is < $29, and display a final total



Shopping Cart: A ShoppingCart contains a Map of pid - CartItem pairs. (There cannot be 2 CartItem's with the same pid. If addToCart does add an pid, then new quantity is added to the existing quantity.)

CartItem: A CartItem "knows" the Product and the quantity that the shopper wishes to purchase.

Product: (For the purposes of this lab exercise) a Product knows its description and its regular price.

Exercise 2:

Add Inventory tracking. For brevity / simplicity assume that your store never runs out of inventory. Assume an initial inventory of 100 items for each Product.

Inventory will update as Products are added and removed from ShoppingCarts. For example, when 5 of pid 111 are added to cartId 2, the inStock value for pid 111 is decreased by 5 and the reserved value is increased by 5. etc. etc.

In addition, your OnlineStore should be able to dumpInventory() to display the current state of its Inventory.

I found sequence diagrams very useful here!

Note that running your code with the Test1 main in the lab5 directory should produce output very much like that in out1.txt.

Submit:

This assignment is due at the beginning of the Tuesday lab class after the reading break (March 6) at 3:30 p.m. - and the submit program will enforce this

• Submit your source code electronically using the command
  ~hohman/bin/submit 331 lab5
• Also hand-in a "good enough" class diagram for your code, and a sequence diagram for the checkout "use case".