The document outlines the design and development phases of an e-commerce website for selling a product online, detailing requirements such as inventory management, customer registration, and sales tracking. It discusses use cases, high-level design components, and detailed designs that include checkout processes and discount applications, followed by various coding methodologies including pseudocode and flowcharts. Additionally, it addresses problem-solving strategies through logic structures and abstraction in design to enhance code organization and functionality.

1. Contents
Phase 1: Design Concepts 2
Project Description 2
Use Cases3
Data Dictionary 4
High Level Design Components 5
Detailed Design: Checkout 7
Diagrams 7
Design Analysis 8
Detailed Design: Product Research 9
Diagrams 9
Design – Using Pseudocode 10
Product Profit 10
Phase 2: Sequential Logic Structures 11
Design 11
Product Profit 11
Phase 3: Problem Solving with Decisions12
Safe Discount 12
Return Customer Bonus 13
Applying Discounts 14
Phase 4: Problem Solving with Loops 15
Total order 15
Problems to Solve 16
Calculate Profits 16
Rock, Paper, Scissors 18
Number Guessing Game 20
Phase 5: Using Abstractions in Design 22
Seeing Abstractions 22
Refactoring 22
Phase 1: Design ConceptsProject Description
Although we may be late to the game, we will nevertheless join
the world of e-commerce to sell our fantastic product on the

2. Internet. To do so, we need a Web site that will allow for
commerce and sales. To be quick about it, we require the
following:
· Searchable inventory and shopping pages
· A shopping cart
· A place for customers to register when they make purchases
· A checkout process to make the purchase
Within this main process, there are a bunch of other needs that
must be met, as follows:
· We want to track the date of the last purchase a customer
make so we can offer incentives and discounts based on the last
time they shopped.
· We will offer sales based on the number of different items that
a person purchases.
· We will also give discounts for bulk orders a discount when a
person buys many of the same item
In addition to sales feature, the solution must provide the ability
to manage and research the sales of products. It must include
the following:
· Must be able to add, update and remove product inventory in
real time on the site
· Needs to have research capabilities to determine how well a
product is selling, such as the following:
· How often the item is viewed, added to shopping carts, and
then purchased
· How a price change affects sales and profit
Use Cases
From the description above, we can relate this to the following
use cases, which describe how the user will interact with our
system. Each use case is a set of screens that the users would
interact with to accomplish something they need on the site.
In addition to the customer’s activity, the solution will allow
Sales Analysts to manage and research product sales.
Data Dictionary

3. Variable Name
Type
Description
todaysDate
Date
Today’s date, when the program is running
creationDate
Date
The date the customer created their account
priorPurchases
Integer
Number of Purchases this customer has made in the past
lastPurchaseDate
Date
The date of the last purchase the customer made
lineItemPrice
Array
The price of each line item the customer has added to the cart
lineItemQuantity
Array
The quantity of each line item the customer has added to the
cart
membershipLevel
Integer
The account nature of the customer
1 – Guest
2 – Registered
3 – Preferred
totalPurchaseAmount
Double
The cost of all the items in their current purchase
salesTaxRate
Double
The sales tax to be charged on a purchase
productCategory
Integer

4. An indicator of the category of the product
1 – Consumer Goods
2 – Electronics
3 – Clothing
productPrice
Double
The price of the product as sold to the customer
wholesalePrice
Double
The price at which we purchase the product
numberInCarts
Integer
The total number of times this product has been added to a
shopping cart
numberOfPurchases
Integer
The number of times this product has been purchased
allProductSalesNumbers
Array
A list for each product of the number of times a product has
sold
allProductPrices
Array
A list for each product of the product price
allProductWholesalePrices
Array
A list for each product of the product wholesale price
High Level Design Components
Our architects have created the following components to be
realized by our development team in meeting the use cases
above.
SearchEngine
ProductInventory
ShoppingCart
CardProcessing

5. Purchasing
CustomerManager
UserSecurity
Fill out the following table to describe which components are
used by each use case and how each component will help realize
the use case:
Use Case
Component
Services Provided
Search/Browse Inventory
ProductInventory
Provides access to the database of inventory of all products and
their descriptions and prices and such.
SearchEngine
Allows for searching on many criteria within the product
database
Register As Customer
CustomerManager
Create and manage customer profile and personal information
UserSecurity
Provide security solutions for the visitors to the site
Choose Products
<fill me>
<fill me>

6. Checkout
<fill me>
<fill me>
Apply Discounts
<fill me>
<fill me>
Manage Products
<fill me>
<fill me>

7. Research Sales
<fill me>
<fill me>
Detailed Design: Checkout
Diagrams
We could realize this design as either structured or Object-
Oriented given the following design diagrams.
calculate
OrderTotal
Calculate Subtotal
bigBuyer
Discount
bulkBuyer
Discount
returnCustomer
Bonus
daysSinceLast Purchase

8. Figure 1 Structure Design for calculateOrderTotal
Figure 2: Sequence Diagram for calculateOrderTotal
;Order
;DiscountManager

9. ;Customer
;Taxes
bigBuyerDiscount()
bulkBuyerDiscount()
returnCustomerBonus()
daysSinceLastPurchase()
calculateSubtotal()
Design Analysis
Given the designs above, we need to analyze which approach we
should take and how the code realization will differ. Structure
Design
· Describe the implementation of the structure design in Figure
1 and how it relates to the Checkout use case.
· What procedures and functions are being created in the
design?
· What data would be passed between these procedures and
functions?Object-Oriented Design
· Describe the implementation of the object-oriented design in
Figure 2 and how it relates to the Checkout use case.
· What methods are being created in the design?
· What data would be passed between these
methods?Comparison
· How do these approaches (Structured versus OO) differ?
· How much will the detailed implementation when we get to
code differ because of the high level design approach we
choose?
Detailed Design: Product Research
Diagrams
For the product research use case, take a stab at either a
structured design diagram or a sequence diagram that would
fulfill at least part of the functionality of the use case. We will
compare what you create here to the detailed design we create

10. through the rest of the course as a way of measuring your
progress.
· Provide a diagram of your choice here to show a flow for
researching products.
The exact details are flexible within the description of the
functionality, so do your best to create a flow that looks like a
code solution using the components above or ones you think you
need. This is practice that will give you a measuring stick for
your learning as we see problems later in the course related to
this system.
Design – Using Pseudocode
Product ProfitDescription
It is important to know the profit each product is providing to
the bottom line. Given that we know the wholesale cost, the
retail cost to consumers and the number of items we have sold,
calculate the profit for a given product. Pseudocode
function productProfit(productPrice : Double,
wholesalePrice : Double,
numberOfPurchases : Integer)
Return Double
<add your logic here>
End function
Phase 2: Sequential Logic StructuresDesign
Product ProfitDescription
Continuing with the same example of calculation product profit,
utilize the same scenario to create a flowchart.
Description - It is important to know the profit each product is
providing to the bottom line. Given that we know the wholesale
cost, the retail cost to consumers and the number of items we
have sold, calculate the profit for a given product. Flowchart
<insert here>Additional Pseudocode
Discuss how input/output, operators, and expressions are

11. presented in pseduocode as well as how they are used to
accommodate needs for sequential logic within business
applications. Additionally, discuss how various data types may
be used within sequential logic structures.
Phase 3: Problem Solving with Decisions
Safe DiscountDescription
We want to ensure that the system will not accidentally discount
a product below the price that it is purchased for. Thus, we want
an operation to ensure that, when a discount is applied, it
always stays more than the original purchase price.
Sample data could include the following:
· A product at $10 with a wholesale price of $5 and a discount
of 10% returning $9.
· A product at $10 with a wholesale price of $6 and a discount
of 50% returning $6.Pseudocode
function applyDiscount(productPrice : Double,
wholesalePrice : Double,
discount : Double)
Return Double
<add your logic here>
End functionFlowchart
<insert here>
Return Customer BonusDescription
We want to reward customers for returning to make a purchase.
To incentivize, they receive a bonus discount as by the
following levels.
· Less than a week = 10%
· More than 6 months = 6%
· Otherwise, 1% for each month (consider a month to be 30
days)
Sample data for testing:
Scenario

12. todaysDate
lastPurchaseDate
totalPuchaseAmount
Return amount
1
2/1/2014
1/25/2014
$100
$90
2
2/1/2014
3/17/2013
$100
$94
3
2/1/2014
12/11/2013
$100
$TBD
4
2/1/2014
9/25/2013
$100
$ TBD
Flowchart
<insert here>Pseudocode
function returnCustomerBonus (todaysDate : Date,
lastPurchaseDate : Date,
totalPurchaeAmount : Double)
returns double
<add your logic here>
end function
Applying DiscountsDescription
A customer receives his or her discount based on his or her

13. membership status. Preferred members receive a return member
bonus, and all registered members receive a bulk discount, but
guests do not receive any discounts.
This should reuse the discounts from the prior work, so test
cases from there would apply. Just make sure that guests receive
no discount, registered members just get a discount for any
items for the bulk discount, and preferred members get both the
bulk discount and the return customer bonus. Flowchart
<insert here>Pseudocode
function applyDiscounts (todaysDate : Date,
lastPurchaseDate : Date,
totalPurchaseAmount : Double,
membershipLevel : Integer)
returns double
<add your logic here>
end function
Phase 4: Problem Solving with Loops
Total orderDescription
Once the final prices are calculated for each product, we need to
total up the order and then add in sales tax. We need to go
through the line items in an order and figure out the final
price.Flowchart
Create variable Double: subtotal
Return
calculateSubtotal (subtotal, salesTaxRate)
Subtotal = subtotal +
lineItemTotal
index = each item in lineItemPrice
lineItemTotal=
lineItemPrice[index] *
lineItemQuantity[index]

14. Pseudocode
function totalOrder (lineItemPrice: Array,
lineItemQuantity : Array,
saleTaxRate : Double)
returns double
Create variable Double : subtotal
for (index = each item in lineItemPrice)
lineItemTotal = lineItemPrice[index] *
lineItemQuantity[index]
subtotal = subtotal + lineItemTotal
end loop
return calculateSubtotal (subtotal, salesTaxRate)
end function
Problems to Solve
Fill in the following table by walking through the logic above.
The idea is to analyze how the chart and pseudocode was
created, because you will be doing this in a few minutes, so do
not just jump to the easy answer. Follow the steps as if you are
the computer executing the software designed.
Problem
lineItemPrice
lineItemQuantity
saleTaxRate
Return amount
1
[5.50, 3.00, 2.25]
[12, 3, 10]
5%
2
[5.50]
[5]
5%

15. 3
[]
[]
5%
Calculate ProfitsDescription
Given the list of all the product prices and wholesale prices as
well as a list of all the items sold for each product calculate the
net profit for all the products.Flowchart
<insert here>Pseudocode
function totalProfits (allProductSalesNumbers: Array,
allProductPrices : Array,
allProductWholesalePrices : Array)
returns double
<add your logic here>
end function
Rock, Paper, ScissorsDescription
To expand further, we want to try out logic in interacting with
users. Here is a sample of a game, using loops and decisions to
allow a person to play rock-paper-scissors with a
computer.Pseudocode
We have a helper function that we will use here that tells us
who won. It will result in +1 if the player wins, a -1 if the
computer wins, and a 0 if it is a tie.
function compareOutcome(computerMove: Integer,
playerChoice : Integer) returns Integer
And the main flow of our logic is as such.
while (true)
Integer : computerChoice = randomChooser()
Integer : playerEntry = prompt user to enter a value

16. If (playerEntry is not a valid input)
Prompt user they have picked a bad number and
try again
Else
Integer : outcome = compareOutcome(computerMove,
playerEntry)
If (outcome = 0)
Prompt user it is a tie, and try again
Else if (outcome = -1)
Prompt user they lost
Break out of loop
Else
Prompt user they won
Break out of loop
End if
End if
end loopFlowchart
true
playerEntry is not a valid input
outcome =
0
outcome =
-1
Integer : computerChoice = ramdonChooser()
Integer : playerEntry = prompt user to enter a value
Prompt user they have picked a bad number and try again
Integer : outcome = compareOutcome(computerMove,
playerEntry)
Prompt user it is a tie, and try again
Prompt user they lost
Break
Prompt user they won

17. End of game
Break
Note: In this case, note the advantages and disadvantages of
flowcharts and pseudocode. The flowchart is easy to follow the
logic for one scenario, but does it make it easier or harder to
understand the code as a whole? There is no strict answer, but
one that tells you a bit about your way of thinking and personal
preference.Interaction Scenario
For either of the solutions above, follow the logic and map out
your interaction step-by-step, trying to exercise all paths of the
logic. You will have to take at least 2 times through the game to
map all scenarios.
Scenario 1
Step
User Input
System Response
1
User chooses 50
System says lower
2
…
..
3
4
Scenario 2
Step
User Input
System Response
1

18. 2
3
4
(copy and add more if needed/desired)
Number Guessing GameDescription
Now it is your turn to try out user interaction with a simple
game. This goes back to the number guessing game. The user
will input a number each time, say between 1 and 100. The
computer will randomly select 1 number each game (note this is
different than the example above where it selects a new answer
each round), and the game continues until the user guesses the
right number.
Like above, your solution should accommodate for invalid
input, but do not worry about how to make that logic work for
now. Your solution should give some hints though if the guess
the user made was too high or too low, to help them on their
way.Flowchart
<Your solution here>Pseudocode
<your solution here>
Phase 5: Using Abstractions in DesignSeeing Abstractions
Throughout this course, we have been realizing the detailed
design for the pieces of the whole picture we started with at the
beginning of the course. We have built many abstractions, so
let’s go back and document what we have found and see the
abstractions we have created.
Abstraction Name
Parameter List

19. Scope/Purpose
calculateSubtotal
(totalPurchaseAmount :double,
salesTaxRate : double)
Applies sales tax and computes the final amount due
<keep going>

20. Refactoring
Sometimes it is easy to see how the whole solution can be
broken into pieces, and other times it is done as you see
abstractions and opportunities for reuse in the resulting design.
This is called refactoring. For the pseudocode you see below,
look for abstractions you could create and create a flowchart
using your simplifications.
Psuedocode in Need of Refactoring
Array : namesInSystem
Array : phoneNumbersInSystem
String : nameInput
While (nameInput is not valid)
nameInput = prompt user for input
if (nameInput is provided and not blank)
break out of loop
end loop
Prompt user the input is required and not blank
End loop
Integer : indexForName = -1
For (index = all items in namesInSystem
If (nameInput = namesInSystem[index])
indexForName = index
end if
End loop
If (indexForName = -1)
Prompt user “We cannot find your account, please call us”

21. Else
String : phoneNumberInput
While (phoneNumber is not valid)
phoneNumber = prompt user for input
if (phoneNumber is provided and not blank)
break out of loop
end loop
Prompt user the input is required and not blank
End loop
If (phoneNumber =
phoneNumbersInSystem[indexForName])
Prompt “we found your account welcome”
Else
Prompt “we cannot validate your account, try
again later”
End if
End ifRefactored Flowchart
The above pseudocode is long, but you can omit much of the
details. You can accomplish the same logic removing more than
30 lines. You do not have to show all of the details removed if
moved into an abstraction, simply name the abstraction and
define the parameters to be passed to the call replacing the lines
of code.
<insert your flowchart here>
Contents
Phase 1: Design Concepts 2
Project Description 2
Use Cases3
Data Dictionary 4
High Level Design Components 5
Detailed Design: Checkout 7
Diagrams 7

22. Design Analysis 8
Detailed Design: Product Research 9
Diagrams 9
Design – Using Pseudocode 10
Product Profit 10
Phase 2: Sequential Logic Structures 11
Design 11
Product Profit 11
Phase 3: Problem Solving with Decisions12
Safe Discount 12
Return Customer Bonus 13
Applying Discounts 14
Phase 4: Problem Solving with Loops 15
Total order 15
Problems to Solve 16
Calculate Profits 16
Rock, Paper, Scissors 18
Number Guessing Game 20
Phase 5: Using Abstractions in Design 22
Seeing Abstractions 22
Refactoring 22
Phase 1: Design ConceptsProject Description
Although we may be late to the game, we will nevertheless join
the world of e-commerce to sell our fantastic product on the
Internet. To do so, we need a Web site that will allow for
commerce and sales. To be quick about it, we require the
following:
· Searchable inventory and shopping pages
· A shopping cart
· A place for customers to register when they make purchases
· A checkout process to make the purchase
Within this main process, there are a bunch of other needs that
must be met, as follows:
· We want to track the date of the last purchase a customer
make so we can offer incentives and discounts based on the last

23. time they shopped.
· We will offer sales based on the number of different items that
a person purchases.
· We will also give discounts for bulk orders a discount when a
person buys many of the same item
In addition to sales feature, the solution must provide the ability
to manage and research the sales of products. It must include
the following:
· Must be able to add, update and remove product inventory in
real time on the site
· Needs to have research capabilities to determine how well a
product is selling, such as the following:
· How often the item is viewed, added to shopping carts, and
then purchased
· How a price change affects sales and profit
Use Cases
From the description above, we can relate this to the following
use cases, which describe how the user will interact with our
system. Each use case is a set of screens that the users would
interact with to accomplish something they need on the site.
In addition to the customer’s activity, the solution will allow
Sales Analysts to manage and research product sales.
Data Dictionary
Variable Name
Type
Description
todaysDate
Date
Today’s date, when the program is running
creationDate
Date
The date the customer created their account
priorPurchases
Integer

24. Number of Purchases this customer has made in the past
lastPurchaseDate
Date
The date of the last purchase the customer made
lineItemPrice
Array
The price of each line item the customer has added to the cart
lineItemQuantity
Array
The quantity of each line item the customer has added to the
cart
membershipLevel
Integer
The account nature of the customer
1 – Guest
2 – Registered
3 – Preferred
totalPurchaseAmount
Double
The cost of all the items in their current purchase
salesTaxRate
Double
The sales tax to be charged on a purchase
productCategory
Integer
An indicator of the category of the product
1 – Consumer Goods
2 – Electronics
3 – Clothing
productPrice
Double
The price of the product as sold to the customer
wholesalePrice
Double
The price at which we purchase the product
numberInCarts

25. Integer
The total number of times this product has been added to a
shopping cart
numberOfPurchases
Integer
The number of times this product has been purchased
allProductSalesNumbers
Array
A list for each product of the number of times a product has
sold
allProductPrices
Array
A list for each product of the product price
allProductWholesalePrices
Array
A list for each product of the product wholesale price
High Level Design Components
Our architects have created the following components to be
realized by our development team in meeting the use cases
above.
SearchEngine
ProductInventory
ShoppingCart
CardProcessing
Purchasing
CustomerManager
UserSecurity
Fill out the following table to describe which components are
used by each use case and how each component will help realize
the use case:
Use Case
Component
Services Provided

26. Search/Browse Inventory
ProductInventory
Provides access to the database of inventory of all products and
their descriptions and prices and such.
SearchEngine
Allows for searching on many criteria within the product
database
Register As Customer
CustomerManager
Create and manage customer profile and personal information
UserSecurity
Provide security solutions for the visitors to the site
Choose Products
<ProductSelection>
<Allows customers to choose and select products>
Checkout
<ShoppingCart>
<Allows customers to view items added and begin payment
method via credit card or other online payment services>

27. Apply Discounts
<Discounts>
<Allows customer to apply a valid promotional code given by
the company to reduce the original price of a product>
Manage Products
<ManageItems>
<Allows customers to increase, decrease or remove items from
the Shopping Cart>
Research Sales

28. <ProductsSold>
< The number of times this product has been purchased >
Detailed Design: Checkout
Diagrams
We could realize this design as either structured or Object-
Oriented given the following design diagrams.
calculate
OrderTotal
Calculate Subtotal
bigBuyer
Discount
bulkBuyer
Discount
returnCustomer
Bonus
daysSinceLast Purchase

29. Figure 1 Structure Design for calculateOrderTotal
Figure 2: Sequence Diagram for calculateOrderTotal
;Order
;DiscountManager
;Customer
;Taxes
bigBuyerDiscount()
bulkBuyerDiscount()
returnCustomerBonus()
daysSinceLastPurchase()
calculateSubtotal()

30. Design Analysis
Given the designs above, we need to analyze which approach we
should take and how the code realization will differ. Structure
Design
· Describe the implementation of the structure design in Figure
1 and how it relates to the Checkout use case.
Figure 1 shows how discounts and bonuses are given and the
criteria they are given on. There are discounts for bulk orders,
big buyers, and returning customers. Through this checkout
process, the discount depends on the customer and the order
being purchased.
· What procedures and functions are being created in the
design?
In Figure 1 above, the design shows how the customer and their
purchase coincides with one another to determine a finalized
price. This includes addition, i.e. shipping and tax, and
subtraction i.e. discounts.
· What data would be passed between these procedures and
functions?
The data that would be passed between these procedures and
functions would be what type of discount you would receive if
you are a Bulk-Buyer, Big-Buyer, or Returning customer. Also,
purchase history and bonuses are identified through this process
as well. Object-Oriented Design
· Describe the implementation of the object-oriented design in
Figure 2 and how it relates to the Checkout use case.
Figure 2 shows somewhat of a process timeline that you can
expect to go through depending on what type of customer you
are. For instance if you are a one-time customer you will by-
pass all discounts and your order will be paid in full including
taxes, whereas if you are a returning bulk-buyer you will be
presented with a bulk-buyer discount.
· What methods are being created in the design?

31. The methods that are being created in the design are that to
show the process in which the order total will be calculated.
Depending on what kind of customer you are depends on your
order total.
· What data would be passed between these methods?
The data that is passed between these methods is who will
receive a discount and at what point in the Order Total process
does the specified buyer receive their discount or if the buyer
receives a discount at all. Comparison
· How do these approaches (Structured versus OO) differ?
One big difference between both approaches is that Figure
1calculates the order total first before discounts and then Figure
2 calculates order total after all the discounts have been
applied.
· How much will the detailed implementation when we get to
code differ because of the high level design approach we
choose?
It will differ because of the process being coded. The designs
are similar but have small differences. Even though the
differences are small, the codes have to process each in a
different way, so that means the code implementation will be
significantly different.
Detailed Design: Product Research
Diagrams
For the product research use case, take a stab at either a
structured design diagram or a sequence diagram that would
fulfill at least part of the functionality of the use case. We will
compare what you create here to the detailed design we create

32. through the rest of the course as a way of measuring your
progress.
· Provide a diagram of your choice here to show a flow for
researching products.
The exact details are flexible within the description of the
functionality, so do your best to create a flow that looks like a
code solution using the components above or ones you think you
need. This is practice that will give you a measuring stick for
your learning as we see problems later in the course related to
this system.
Customer
Registration
Calculate Tool
Discount
Product
Selection
Search
Inventory
Inventory
Design – Using Pseudocode
Product ProfitDescription
It is important to know the profit each product is providing to
the bottom line. Given that we know the wholesale cost, the
retail cost to consumers and the number of items we have sold,
calculate the profit for a given product. Pseudocode
function productProfit(productPrice : Double,
wholesalePrice : Double,
numberOfPurchases : Integer)
Return Double
Profit = (productPrice – wholesalePrice) ⃰
numberOfPurchases
End function