Kata09: Back to the Checkout

Table of Contents

• Description
• Architecture
• Usage
• Test-driven development
• Code
• Technologies Used

Description:

• Refer CodeKata for the complete Problem Description

• Summary of problem

  • Individual letters of the alphabet (A, B, C, and so on) are used to identify goods/items in a store.
  • Goods are priced individually.
  • In addition, some items are multi-priced: buy n of them, and they'll cost you y cents. (Eg: item 'A' might cost 50 cents individually. But, buy three 'A's and they'll cost you $1.30).
  • checkout accepts items in any order. So that if we scan a B, an A, and another B, we'll recognize the two B's and price them at 45 (for a total price so far of 95).
  • Because the pricing changes frequently, we need to be able to pass in a set of pricing rules each time we start handling a checkout transaction.
  • This week's prices are as follows:

  Item   Unit Price      Special Price
  -------------------------------------
    A      50             3 for 130
    B      30             2 for 45
    C      20
    D      15

Architecture

kata-09
├───images
├───pom.xml
├───README.md
├───src
│   ├───main
│   │   └───java
│   │       └───com.codekata.kataNine
│   │       │       ├───CheckOut.java
│   │       │       └───KataApp.java      <-- uses KataNineUtil to set up CheckOut
│   │       │
│   │       ├───com.codekata.model
│   │       │       └───PricingRule.java
│   │       │
│   │       └───com.codekata.util
│   │               └───KataNineUtil.java <-- define pricing rules here
│   │
│   └───test
│       └───java
│           └───com.codekata.kataNine
│                   └───CheckOutTest.java
│
└───target
    └───kataNine-0.0.1-SNAPSHOT.jar

Usage

• Download the jar file from here.
• Navigate to the directory where the jar file is downloaded in terminal.
• Start the application using the code java -cp kataNine-0.0.1-SNAPSHOT.jar com.codekata.kataNine.KataApp

Test-driven development

• Set of JUnit tests for CheckOut.java can be found here.
• The @BeforeEach method is used to initialize the CheckOut object.
• items are added to the cart using the scanItem() method and the actual and expected totals are compared.

Code

• Different pricing rules can be defined by instantiating the PricingRule.java class
• KataNineUtil.java is used to define unit pricing and special pricing rules.
• A Screenshot of the interface for the checkout is shown below

Technologies Used:

• Java 8
• Maven
• JUnit 5
• Eclipse IDE