To Dukascopy Support,

I have an automated strategy based on momentum. Here is the main code.

public void onTick(Instrument instrument, ITick tick) throws JFException {
        if (instrument != this.instrument) {
            return;
        }

        if (!isActive(order)) {
            order = null;
        } else if(order.equals(IOrder.State.CREATED)) {
            return;
        }           
        
        double[] mom1 = indicators.mom(instrument, selectedPeriod1, offerSide, appliedPrice, momPeriod, filter, 1, tick.getTime(), 0);       
        
        if (order.isLong() && (mom1[0] < -0.0005)) {
            closeOrder(order);      
        }
        
        if (!order.isLong() && (mom1[0] > 0.0005)) {
            closeOrder(order);  
        }
        
        
        if (mom1[0] > 0.0005) {
            if (order == null || !order.isLong()) {
            closeOrder(order);
            order = submitOrder(OrderCommand.BUY, instrument);
            }
        }
        
        if  (mom1[0] < -0.0005) {
            if (order == null || order.isLong()) {
            closeOrder(order);
            order = submitOrder(OrderCommand.SELL, instrument);
            }  
         }   
      }

When I test this strategy on the historical tester, it shows the following error



I understand that there is an error on line 102. This is code on line 102.

if (order.isLong() && (mom1[0] < -0.0005)) {
            closeOrder(order);      
        }

But I don't understand what is wrong. Kindly tell me what is the mistake.

Regards,

Terry.

Probably your order variable is null. So accessing its isLong() throws the exception.

Also, this might be problematic:


As closeOrder(order) will be called when order=null.
Maybe that is not an issue for the API to call closeOrder(null), and it won`t throw exception, but this is bad coding.