The hotel is not airside. You clear immigration and customs first. If you need a visa, the voucher is provided at check in and you would go to a desk at the far end of the arrival hall before immigration desks to receive it. After, if in F/J, go to the chauffeur drive desk, if in Y follow the signs to the shuttle and be taken to the hotel reception directly and check in. You will have the hotel until about 2 hours before departure when the shuttle/car will take you back to the airport and you will go through exit immigration.