KrakenMarketDataServiceRaw krakenMarketDataService = (KrakenMarketDataServiceRaw) krakenExchange.getPollingMarketDataService();
KrakenServerTime serverTime = krakenMarketDataService.getServerTime();
System.out.println(serverTime);
KrakenAssets assets = krakenMarketDataService.getKrakenAssets();
System.out.println(assets);
KrakenSpreads spreads = krakenMarketDataService.getKrakenSpreads(Currencies.BTC, Currencies.USD);
System.out.println(spreads);
}