private static void addPrefixed(PrefixedUnit unit) { Map<Prefix, PrefixedUnit> basicUnitPrefixes; if (UnitFactory.PREFIXED.containsKey(unit.getBaseUnit())) { basicUnitPrefixes = UnitFactory.PREFIXED.get(unit.getBaseUnit()); } else { basicUnitPrefixes = new HashMap<Prefix, PrefixedUnit>(); UnitFactory.PREFIXED.put(unit.getBaseUnit(), basicUnitPrefixes); } basicUnitPrefixes.put(unit.getPrefix(), unit); }