@Override
 public void createQuantity(
     final PersistentAbsUnit unit, final common.Fraction amount, final Invoker invoker)
     throws PersistenceException {
   final java.sql.Date now = new java.sql.Date(new java.util.Date().getTime());
   final PersistentCreateQuantityCommand command =
       model.meta.CreateQuantityCommand.createCreateQuantityCommand(amount, now, now);
   command.setUnit(unit);
   command.setInvoker(invoker);
   command.setCommandReceiver(getThis());
   model.meta.CommandCoordinator.getTheCommandCoordinator().coordinate(command);
 }
 @Override
 public void sub(
     final PersistentAbsQuantity minuend,
     final PersistentAbsQuantity subtrahend,
     final Invoker invoker)
     throws PersistenceException {
   final java.sql.Date now = new java.sql.Date(new java.util.Date().getTime());
   final PersistentSubCommand command = model.meta.SubCommand.createSubCommand(now, now);
   command.setMinuend(minuend);
   command.setSubtrahend(subtrahend);
   command.setInvoker(invoker);
   command.setCommandReceiver(getThis());
   model.meta.CommandCoordinator.getTheCommandCoordinator().coordinate(command);
 }
 @Override
 public void mul(
     final PersistentAbsQuantity factor1,
     final PersistentAbsQuantity factor2,
     final Invoker invoker)
     throws PersistenceException {
   final java.sql.Date now = new java.sql.Date(new java.util.Date().getTime());
   final PersistentMulCommand command = model.meta.MulCommand.createMulCommand(now, now);
   command.setFactor1(factor1);
   command.setFactor2(factor2);
   command.setInvoker(invoker);
   command.setCommandReceiver(getThis());
   model.meta.CommandCoordinator.getTheCommandCoordinator().coordinate(command);
 }
 @Override
 public void div(
     final PersistentAbsQuantity dividend,
     final PersistentAbsQuantity divisor,
     final Invoker invoker)
     throws PersistenceException {
   final java.sql.Date now = new java.sql.Date(new java.util.Date().getTime());
   final PersistentDivCommand command = model.meta.DivCommand.createDivCommand(now, now);
   command.setDividend(dividend);
   command.setDivisor(divisor);
   command.setInvoker(invoker);
   command.setCommandReceiver(getThis());
   model.meta.CommandCoordinator.getTheCommandCoordinator().coordinate(command);
 }
 @Override
 public void add(
     final PersistentAbsQuantity summand1,
     final PersistentAbsQuantity summand2,
     final Invoker invoker)
     throws PersistenceException {
   final java.sql.Date now = new java.sql.Date(new java.util.Date().getTime());
   final PersistentAddCommand command = model.meta.AddCommand.createAddCommand(now, now);
   command.setSummand1(summand1);
   command.setSummand2(summand2);
   command.setInvoker(invoker);
   command.setCommandReceiver(getThis());
   model.meta.CommandCoordinator.getTheCommandCoordinator().coordinate(command);
 }