public boolean renewRole(SorRole role) {
    final Calendar cal = Calendar.getInstance();

    // TODO need to read configuration data for setting the default renewal date for this role type.
    // hard code to 6 months for now.
    cal.add(Calendar.MONTH, 6);
    role.setEnd(cal.getTime());
    return true;
  }
 public boolean expireRole(SorRole role) {
   role.setEnd(new Date());
   return true;
 }