HashingAlgorithm
Returns an instance of MessageDigest
Returns an instance of MessageDigest
Note that this is a method on purpose: getInstance returns a new instance of the algorithm requested. This is recommended because the object returned is mutable but is not thread safe, so we would need to synchronise method calls (e.g. digest) ourselves if we want to use the same instance with multiple threads.
Sealed HashingAlgorithm trait to prevent users from shooting themselves in the foot at runtime by specifying a crappy/unsupported algorithm name
The name should be a valid MessageDigest algorithm name.Implementing child classes/objects should refer to this list for proper names:
http://docs.oracle.com/javase/6/docs/technotes/guides/security/StandardNames.html#MessageDigest