Detailed Use Case Analysis: POS and Stock Control System for Business

This case study provides a detailed use case analysis of a Point of Sale (POS) and Stock Control System. It outlines the principal actor (Cashier) and stakeholders (Cashier, Salesperson, Customer, Company, Federal government Tax Agencies, Payment Authorization Program), detailing their interests. The analysis covers preconditions, success guarantees, and a primary success scenario involving customer purchases, product entry, total calculation, payment processing, and invoice generation. Extensions are explored, including error handling for various scenarios such as program failures, broken identifiers, item removals, sale cancellations, price overrides, and discount applications. Special requirements like touch screen UI, credit authorization response time, and system recovery are also specified. The document further presents the same content in a two-column format emphasizing the interaction between actors and the system.

Use Case: POS and Stock Control System

Principal Actor: Cashier
Stakeholders plus Interests:
- Cashier: Desires accurate, fast entry, with no payment errors, as money drawer shortages are
subtracted from his/her salary.
: Salesperson: Wants sales commission rates updated.
- Customer: Desires purchase and fast services with minimal effort. Desires proof of purchase to
support comes back.
- Company: Wants to precisely record transactions and fulfill customer interests.
Desires some fault tolerance to permit sales capture even if machine components (e. g., remote
control credit validation) are not available. Desires fast and automatic upgrade of supply and
accounting.
o Federal government Tax Agencies: Want to gather tax from every purchase.
o Payment Authorization Program: Wants to receive digital consent requests in the correct
file format and protocol. Really wants to accurately account for their payables to the
store.
Preconditions: Cashier is identified plus authenticated.
Success Guarantee (Post conditions): Sale is saved. Taxes are correctly calculated. Accounting
and Inventory are usually updated. Commissions recorded. Invoice is generated. Payment
consent approvals are recorded.

Primary Success Scenario (or Fundamental Flow):
1. Customer gets to POS checkout with items and/or services to purchase.
2. Cashier starts a new selling.
3. Cashier enters product identifier.
4. System information sale line item plus presents item description, cost, and running total.
Cost calculated from a set associated with price rules.

Cashier repeats steps 3-4 until signifies done.
5. System provides total with taxes determined.
6. Cashier tells Client the total, and asks for transaction.
7. Customer pays plus System handles payment.
8. System logs completed selling and send sale plus payment information to the exterior
Accounting system (for construction and commissions) and Stock system (to update
inventory).
9. System presents invoice.
10. Customer leaves along with receipt and goods (if any).
Extensions (or Choice Flows):
Any kind of time right time, Program fails:
To support recovery plus correct accounting, make certain all transaction sensitive occasions and
state can be retrieved through any step of the situation.
o Cashier restarts Program, logs in, and demands recovery of prior condition.
o System reconstructs before state.
o System picks up anomalies preventing recovery:
o System signals error towards the Cashier, records the mistake, and enters a thoroughly
clean state.
o Cashier begins a new sale.
Broken identifier:
o System indicators error and rejects access.
There are multiple associated with same item category plus tracking unique item identification
not important (e. h., 5 packages of veggie-burgers):

Cashier can get into item category identifier as well as the quantity.
Customer demands Cashier to remove an item from your purchase:
o Cashier gets into item identifier for elimination from sale.
o Program displays updated running overall.
Customer tells Cashier to cancel sale:
Cashier cancels sale upon System.
Cashier suspends the sale:
Program records sale so that it can be obtained for retrieval on any kind of pas terminal.
The device generated item price is just not wanted (e. g., Client complained about
something and it is offered a lower price):
o Cashier enters override price...
o System gifts new price.
Program detects failure to get in touch with external tax calculation program service:
o Program restarts the service around the POS node, plus continues.
o Program detects that the service will not restart.
Customer says they are entitled to a discount (e. grams. employee, preferred customer):
o Cashier signals discount ask for.
o Cashier enters Consumer identification.
o System provides discount total, based on lower price rules.
Customer states they have credit in their accounts, to apply to the sale:
o Cashier signals credit demand.
o Cashier enters Consumer identification.

o Systems implements credit up to price=0, plus reduces remaining credit.
Customer says they meant to pay by cash yet don't have enough cash:
o Customer uses another payment method.
o Customer tells Cashier in order to cancel sale. Cashier cancels sale on System.
Paying by cash:
o Cashier enters the cash quantity tendered.
o System offers the balance due, and produces the cash drawer.
o Cashier deposits cash tendered plus returns balance in money to Customer.
o Program records the cash payment.

Paying by credit:
o Customer enters their credit score account information.
o System transmits payment authorization request for an external Payment Authorization
Support System, and requests transaction approval.
System picks up failure to collaborate along with external system:
o Program signals error to Cashier.
o Cashier asks Client for alternate payment.
System receives payment authorization and signals approval in order to Cashier.
System gets payment denial:
o Program signals denial to Cashier.
o Cashier asks Client for alternate payment.
o System records the credit score payment, which includes the transaction approval.
o System offers credit payment signature insight mechanism.
o Cashier requests Customer for a credit transaction signature. Customer enters signature
bank.
Paying by check out...
Paying by charge...
Customer presents discount codes:
Before handling transaction, Cashier records each promotion and System reduces cost as
appropriate. System information the used coupons intended for accounting reasons.
o Coupon entered is not for just about any purchased item:
o Program signals error to Cashier.
There are product discounts:

Program presents the rebate discount and forms receipts for every item with a rebate.
Client requests gift receipt (no prices visible):
Cashier requests gift System plus receipt presents it.
Special Requirements:
o Touch screen UI on a large fiat panel monitor. Text should be visible from 1 meter.
o Credit authorization reaction within 30 seconds 90% of the time.
o Somehow, we would like robust recovery when entry to remote services such the supply
system is failing.
o Vocabulary internationalization on the text shown.
o Pluggable business guidelines to be inserting able at actions 3 and 7.
Technologies and Data Variations Listing:
Item identifier joined by bar code laser beam scanner (if bar program code is present) or key pad.
Product identifier may be any UPC, EAN, JANUARY, or SKU coding structure.
Credit score account information entered by cards keyboard or reader.
Credit score payment signature captured in writing receipt. But within 2 yrs, we all predict many
customers will want digital unique capture.
Frequency of Incidence: Could be nearly continuous.
Open up Issues:
o What are the taxes law variations?

o Discover the remote service recuperation issue.
o What modification is needed for different businesses?
o Must a cashier consider their cash drawer if they log out?
o Can the customer directly utilize the card reader, or even does the cashier need to do it?
The Two-Column Deviation
A few prefer the two-column or speaking format, which usually emphasizes the fact that there is
a connection taking place between the actors and the functional system. This is actually the same
content using the two-column format:
o Use Case UC1: Process Sale
o Primary Actor or actress
o Main Achievement Scenario:
Actor Action (or Intention) System Responsibility
o Customer arrives at a passing checkout with goods and services to purchase.
o Cashier starts a new purchase.
3. Cashier enters product identifier. 4. Information each sale line product and presents item
explanation and running total. Cashier repeats steps 3-4 till indicates done 5. Program presents
total with fees calculated.
6. Cashier shows Customer the total and requests payment.
7. Customer will pay.
8. Handles payment.