if (! semester.matches("\\p{Digit}-semestre")) {
if (! semester.matches("\\p{Digit}-[sS][eE][mM][eE][sS][tT][rR][eE]")) {
        public Integer getSemesterNumber() {            if (getSemester() == null) {                return null;            }                        String semester = getSemester();            if (! semester.matches("\\p{Digit}-semestre")) {                return null;            }                        return new Integer(semester.substring(0, 1));        }