How to marshall object casted to his superclass in JAXB

I have generated class BookingStructure that marshalling into

<BookingStructure>
    <elementBookingStructure />
</BookingStructure>

and inherited from him class Booking that marshalling into

<Booking>
    <elementBookignStructure />
    <elementBooking />
</Booking>

I need to marshall Booking like BookingStructure

<BookingStructure>
    <elementBookingStructure />
</BookingStructure>

How can I do this using javax.xml.bind? Thanks