From the Holland America web site....
Except for wine and champagne, guests cannot bring hard alcohol on board for private consumption. Hard alcohol purchased on board in the duty free shops or in port will be collected, stored for safekeeping and delivered to your stateroom on the last day of the voyage.
Guests can bring wine and/or champagne on board at embarkation or purchased in port. A corkage fee of US$18.00 applies to wine and champagne brought to the shipboard restaurants or bars for consumption. Wine and/or champagne brought on board cannot be consumed in any public venue. If a guest is drinking a beverage carried on board and in a public venue they will be asked to return it to their stateroom.