Exercise:

Using Java, write a simple program that calculates the price of a basket of shopping. Items are presented one at a time, in a list, identified by name - for example "Apple" or "Banana".

Multiple items are present multiple times in the list, so for example ["Apple", "Apple", "Banana"] is a basket with two apples and one banana.

Items are priced as follows:

• Apples are 35p each
• Bananas are 20p each
• Melons are 50p each, but are available as 'buy one get one free'
• Limes are 15p each, but are available in a 'three for the price of two' offer

Given a list of shopping, calculate the total cost of those items.

Assumptions:

• shopping list given via text input file passed as argument in command line (see below). valid input files contain one item per row, there is no row number limit Note. Because there is a very high chance a user will just run without providing an input file first, there is one hardcoded default list used instead to omit a dry run :)
• inventory is a singleton class, placeholder for excercise given data

Solution

This is a possible answer to the given exercise: load all items in a list and generate a map of it grouped by item so, for example, the following list:

["Apple", "Apple", "Banana", "Melon", "Melon", "Lime", "Melon", "Lime", "Lime", "Lime"]

is mapped to: basketContents={Lime=4, Apple=2, Melon=3, Banana=1}

then com.cmarina.shopping.ShoppingBasket.computePrice() will do the rest.

Running:

$git clone https://github.com/calinmarina/shopping-basket.git
$mvn clean package

...

$java -jar target/ShoppingCart-1.0-SNAPSHOT.jar
Using hardcoded shopping basket!
You can create text files with items list and start ShoppingApp with that file as commandline parameter
ShoppingBasket [basketContents={Lime=4, Apple=2, Melon=3, Banana=1}]
2.35

Run jUnit tests included:

mvn test