@Override
 public int compareTo(com.poesys.db.dto.IDbDto o) {
   ISubscriptionDescription other = (ISubscriptionDescription) o;
   // Sort on the key. Same semantics as equals and hashCode().
   return other.getPrimaryKey().compareTo(key);
 }
 @Override
 public boolean equals(Object arg0) {
   ISubscriptionDescription other = (ISubscriptionDescription) arg0;
   return other.getPrimaryKey().equals(key);
 }