// Buy.
String orderId = tradeService.buy(MIN_AMOUNT_PER_ORDER.multiply(new BigDecimal("1000")), MIN_PRICE_IN_CNY).getId();
// Cancel.
tradeService.cancelBTCTradeOrder(orderId);
// Sell.
orderId = tradeService.sell(MIN_AMOUNT_PER_ORDER, new BigDecimal(Integer.MAX_VALUE)).getId();
// Cancel.