docs: public Reference getReference() throws NamingException {
      Reference ref = super.getReference();
      ref.add(new StringRefAddr("dataSourceName", dataSourceName));
      if (initialConnections > 0) {
        ref.add(new StringRefAddr("initialConnections", Integer.toString(initialConnections)));
      }
      if (maxConnections > 0) {
        ref.add(new StringRefAddr("maxConnections", Integer.toString(maxConnections)));
      }
      return ref;
    }