The machine can store coffee powder, milk and water. The maximum storage capacity of coffee powder is 500gm, milk is 1 litre and water 2 liters. Each coffee is made by taking 10gm coffee and 0.2 liter of water. For milk coffee it uses 0.4 liter of milk. There should be public behaviours (can be termed as interfaces) for making coffee and filling the ingredients. Besides that there should be interfaces for cleaning machine, loading the machine with full capacity of ingredients and displaying the status of machine which shows the number of coffees made and the status of ingredients in machine at that particular point of time.