udunits/src/main/java/ucar/units/StandardUnitDB.java
private void au(final String name, final String definition,
                  final String symbol, final String plural)
          throws UnitExistsException, NoSuchUnitException,
          UnitParseException, SpecificationException, UnitDBException,
          PrefixDBException, OperationException, NameException,
          UnitSystemException {
    final Unit unit = format.parse(definition, this);
    if (unit == null) {
      throw new NoSuchUnitException(definition);
    }
    addUnit(unit.clone(UnitName.newUnitName(name, plural, symbol)));
  }
private void au(final String name, final String definition,
                  final String symbol, final String plural)
          throws UnitExistsException, NoSuchUnitException,
          UnitParseException, SpecificationException, UnitDBException,
          PrefixDBException, OperationException, NameException,
          UnitSystemException {
    final Unit unit = format.parse(definition, this);
    if (unit == null) {
      throw new NoSuchUnitException(definition);
    }
    addUnit(unit.clone(UnitName.newUnitName(name, plural, symbol)));
  }
private void au ( final String name , final String definition , final String symbol , final String plural ) throws UnitExistsException , NoSuchUnitException , UnitParseException , SpecificationException , UnitDBException , PrefixDBException , OperationException , NameException , UnitSystemException { final Unit unit = format . parse ( definition , this ) ; if ( unit == null ) { throw new NoSuchUnitException ( definition ) ; } addUnit ( unit . clone ( UnitName . newUnitName ( name , plural , symbol ) ) ) ; }
Adds a derived unit to the database.

@param name       The name of the unit.
@param definition The definition for the unit.
@param symbol     The symbol for the unit.
@param plural     The plural form of the name of the unit.
@throws UnitExistsException    Attempt to redefine an existing unit.
@throws NameException          Bad unit name.
@throws UnitParseException     A string specification couldn't be parsed.
@throws SpecificationException Bad string specification.
@throws UnitDBException        Problem with the unit database.
@throws PrefixDBException      Problem with the prefix database.
@throws NameException          Bad unit name.
@throws OperationException     Improper unit operation.
@throws UnitSystemException    Problem with UnitSystem.
Adds a derived unit to the database .