The reference implementation provides a singleton factory accessor class Quantities, like Collections and other similar classes in the JDK. This class is a “convenience” facade over having to retrieve a new instance of QuantityFactory via the SPI for obtaining new Quantity instances. Examples:
Qantity<Time> t = Quantities.getQuantity(12, MILLI(SECOND));
Quantity<Length> len = Quantities.getQuantity(34.5, KILO(METRE));