private void ClearAll() throws ServerException{
PersistenceManager pm = PMF.get().getPersistenceManager();
Query query1 = pm.newQuery(Diagnosis.class);
List<Diagnosis> diagnosis1 = (List<Diagnosis>) query1.execute();
try {
pm.deletePersistentAll(diagnosis1);
} catch(Exception e) {
throw new ServerException(e.toString());
} finally {
pm.close();
}