d2d-cafe

How to run

There is a simple demo Application Runner which simulates a point of sale transaction inside the test folder package au.net.woodberry.d2d.cafe

The CafeDemo.java runner will run a sample point of sale transaction and output a response

Preparing order...
--------
Item            : House blend
Preparation     : Mocha
Size            : Standard
Optional Extras : [Milk, Sugar, Coco powder]
--------
Total cost      : 4.35

Key Design Points

• The solution is kept purposely simple - No 3rd party libraries were ultimately required on the mainline.
• The point of sale solution from a backend perspective is an OrderService that accepts any type of MenuItem.
• The Service, Domain and Repository do not understand the concept of a Coffee. This context is only evident in RepositoryData. This allows for higher order abstractions, for example another type of beverage could be introduced quite easily.
• Conceptually, MenuItem is denoted by items with a ($), MenuItemPreparation, MenuItemExtra are denoted by (+) and MenuItemSize is denoted by (x).

For Example:

MenuItem ($)	MenuItemPreparation (+)	MenuItemExtra (+)	MenuItemSize (x)
Dark roast ($1)	Latte (+ $1.00)	Sugar (+ $0.25)	Large (x1.5)

Quality control

• All unit tests are located in OrderServiceImplTest.
• This test class uses Mockito's @Spy annotation instead of @Mock. Normally, there would be unit tests for the repository layer but as the repositories themselves are essentially mocked through the use of static data, there isn't much value in creating unit tests. The use of spies on the repository classes will still allow for verification and correctness of the service in interacting with the repository.