{
    boolean oldDerived = (eFlags & DERIVED_EFLAG) != 0;
    if (newDerived) eFlags |= DERIVED_EFLAG; else eFlags &= ~DERIVED_EFLAG;
    if (eNotificationRequired())
      eNotify(new ENotificationImpl(this, Notification.SET, EcorePackage.ESTRUCTURAL_FEATURE__DERIVED, oldDerived, newDerived));
  }