public Float getCostOfSousTraitants(CommandesEntity commandesEntity) {
   CoefficientEntity coefficientEntity = coefficientManager.findCurrentCoefficient();
   return coefficientEntity.getStCoef() * this.getSumOfCostByCommandes(commandesEntity);
 }
 public Float getCostOfIntervenants(CommandesEntity commandesEntity) {
   CoefficientEntity coefficientEntity = coefficientManager.findCurrentCoefficient();
   return coefficientEntity.getInterCoef() * this.getSumOfHoursByCommandes(commandesEntity);
 }