final String currentLowerCaseSigla = degree.getSigla().toLowerCase();
final String currentLowerCaseSigla = (degree.getSigla() != null) ? degree.getSigla().toLowerCase() : "";
    private static void updateCache(final Degree degree, final String newLowerCaseSigla) {        final String currentLowerCaseSigla = degree.getSigla().toLowerCase();        synchronized (degrees) {            degrees.remove(currentLowerCaseSigla);            degrees.put(newLowerCaseSigla, new SoftReference<Degree>(degree));        }            }