ExecutionPeriod element = (ExecutionPeriod) iter.next();
IExecutionPeriod element = (IExecutionPeriod) iter.next();
    public List readExecutionPeriodsInTimePeriod(Date start, Date end) throws ExcepcaoPersistencia {        Collection executionPeriods = readAll(ExecutionPeriod.class);           List executionPeriodsAux = new ArrayList();                for (Iterator iter = executionPeriods.iterator(); iter.hasNext();) {            ExecutionPeriod element = (ExecutionPeriod) iter.next();            if(element.getBeginDate().before(end) && element.getEndDate().after(start))                executionPeriodsAux.add(element);        }             return executionPeriodsAux;    }