@Override public BillDto update(BillDto d) { Preconditions.checkArgument(d.getId() != null, "id required"); Bill e = this.getDao().findById(d.getId()); ErrorTypedConditions.checkArgument(e != null, ErrorType.BILL_NOT_FOUND); this.getDao().saveOrUpdate(e); return this.getTransformer().transform(e); }