I\'m using JSR 363 \"Units of Measurement\" with the latest reference implementation:
javax.measure
See the JSR 363 extension module https://github.com/unitsofmeasurement/uom-systems/tree/master/ucum-java8 for UCUM support.
It provides support for the Unified Code for Units of Measure on Java SE 8.
At the moment UCUM is more powerful and extensive, parsing uses a SymbolMap
concept (based on Java ResourceBundles though it is not local-sensitive) so we cannot make it available for the JSR 363 RI. Please use the compatible Java SE 8 port UoM SE if you can.
In UCUM both l (lower case ell) and L are used for liter. The lower case is continental European style, the upper case is US style. Both are equivalent in UCUM. So it's just a style issue.