if (classView.getExecutionPeriodOID().equals(previousExecutionPeriod.getIdInternal())) {
if (previousExecutionPeriod != null && classView.getExecutionPeriodOID().equals(previousExecutionPeriod.getIdInternal())) {
    private void organizeClassViewsNext(HttpServletRequest request, List classViews,            InfoExecutionPeriod previousExecutionPeriod) {        Table classViewsTableCurrent = new Table(5);        Table classViewsTablePrevious = new Table(5);        for (Iterator iterator = classViews.iterator(); iterator.hasNext();) {            ClassView classView = (ClassView) iterator.next();            if (classView.getExecutionPeriodOID().equals(previousExecutionPeriod.getIdInternal())) {                classViewsTablePrevious.appendToColumn(classView.getCurricularYear().intValue() - 1,                        classView);            } else {                classViewsTableCurrent.appendToColumn(classView.getCurricularYear().intValue() - 1,                        classView);            }        }        request.setAttribute("classViewsTableCurrent", classViewsTableCurrent);        request.setAttribute("classViewsTableNext", classViewsTablePrevious);    }