public boolean checkAlreadyEnroled(IGrouping grouping, String studentUsername) throws ExcepcaoPersistencia {
public boolean checkAlreadyEnroled(IGrouping grouping, String studentUsername) {
    public boolean checkAlreadyEnroled(IGrouping grouping, String studentUsername)            throws ExcepcaoPersistencia {        final ISuportePersistente persistentSupport = PersistenceSupportFactory                .getDefaultPersistenceSupport();        final IStudent student = persistentSupport.getIPersistentStudent().readByUsername(                studentUsername);        final IAttends studentAttend = grouping.getStudentAttend(student);        if (studentAttend != null) {            List<IStudentGroup> groupingStudentGroups = grouping.getStudentGroups();            for (final IStudentGroup studentGroup : groupingStudentGroups) {                List<IAttends> studentGroupAttends = studentGroup.getAttends();                for (final IAttends attend : studentGroupAttends) {                    if (attend == studentAttend) {                        return true;                    }                }            }        }        return false;    }