public Unit(Period period, SharedUnit sharedUnit, Unit parent)
{
if (period == null || period.Id == null)
{
throw new ArgumentNullException("period");
}
if (sharedUnit == null || sharedUnit.Id == null)
{
throw new ArgumentNullException("sharedUnit");
}
period.CheckAssigningUnit();
id = new UnitId(period.Id, sharedUnit.Id);
this.sharedUnit = sharedUnit;
this.parent = parent;
customFields = new List <UnitCustomField>();
unitIndexList = new List <UnitUnitIndex>();
}