class DbGatewayContractTest extends GatewayContract {
    Gateway createGatewayReturningNoItem() {
        return new DbGateway(createDaoReturningNoItem());
    }

    Dao createDaoReturningNoItem() {
        return new Dao() {
            public BusinessObject find() {
                return null; // I make an assumption about how Dao signals "no item"
            }
        };
    }
}