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CoinJar Project

AUTHOR: Matheus Felipe - 03/May 2014

The CoinJar supports a volume of 32 oz, Expressed as 946.352946 cubic centimeters in the code.

Each coin (Penny, Nickel, Dime, Quarter, Half Dollar and Dollar) extend the super Class 'Coin', which only responsibility is to calculate
the volume based on the Radius and Height of each coin.

Each sub Class extending Coin has its own getValue() and getVolume() methods, since all coins are different. This way it is easy to go
and change (or add) the specific attributes of each coin without changing the main business logic in an eventual maintenance, code upgrade, etc.
-> Another way of doing this could be used Enum, but I prefer to create separated classes to better represent the intention of the logic.

When a coin is added to the jar using addCoin() it first tries to see if there is still available space to fit your coin. Otherwise it will
throw a significant exception.

The 'reset button', represented by the resetMoneyCount(), will simply zero the value. This reset like a 'withdraw' of all the money.
Otherwise it doesn't make sense to keep coins inside with a zeroed count.

A simple but efficient test suite was included testing the main test cases like:
- Inserting a single coin of a value and asserting the value added.
- Inserting multiple coins and asserting that the sum was correct.
- Inserting multiple coins until the jar can't hold any more coins.
- Resetting the count

IMPORTANT ASSUMPTION:
In a real life CoinJar there is free space among coins that can't be filled at all because of the circular format of the coin.
This CoinJar project only takes into consideration the available volume and the volume of a coin to determine if it will be able to fit inside the jar.