private boolean handleSell(String[] parts) {
        if (parts.length < 3) {
            return false;
        }

        String id = parts[1];
        Stock s = StockControl.queryStock(id);
        if (s == null) {
            return false;
        }
        
        int amount;
        try {
            amount = Integer.parseInt(parts[2]);
        } catch (IllegalArgumentException e) {
            return false;
        }
        
        if (UserControl.canSell(uid, id, amount)) {
            UserControl.sellStock(uid, id, amount);
            /*
            double balance = UserControl.getBalance(uid);
            balance += s.getPrice() * amount;
            UserControl.setBalance(uid, balance);
            */
            int newInventory = s.getInventory() + amount;
            StockControl.setInventory(id, newInventory);
            return true;
        }
        return false;
    }