I have successfully convert / compile my EA code using JForex MQL converter.
And it has running good for 1 day... but when I stopped my running EA and I restarted it with some existing positions in the current demo account, it quickly gives me this error :
java.lang.NullPointerException

And it pointed inside one of my custom functions named FindFirstPrice.

Here's the function code in MQL language :


double FindFirstPrice(int MagicNumber, int OP_Type) {
double l_ord_open_price_0;
int l_ticket_8;
double ld_unused_12 = 0;
int l_ticket_20 = 0;
for (int l_pos_24 = 0; l_pos_24 < OrdersTotal(); l_pos_24++) {
OrderSelect(l_pos_24, SELECT_BY_POS, MODE_TRADES);
if (OrderSymbol() != Symbol() || OrderMagicNumber() != MagicNumber) continue;
if (OrderSymbol() == Symbol() && OrderMagicNumber() == MagicNumber && OrderType() == OP_Type) {
l_ticket_8 = OrderTicket();
if (l_ticket_8 < l_ticket_20) {
l_ord_open_price_0 = OrderOpenPrice();
l_ticket_20 = l_ticket_8;
}
if(l_ticket_20 == 0) {
l_ord_open_price_0 = OrderOpenPrice();
l_ticket_20 = l_ticket_8;
}
}
}
return (l_ord_open_price_0);
}

I hope you can help point out what went wrong in the code.

Hi,

I could probably help if you provide the .mq4 code, and the line number in the java file (within your function) where you have the NPE.
If the EA is confidential, and you are not willing to share it, no problem, I can understand. In that case wait till Support replies.

In JForex platform you can't use trading functions (OrderSelect(), OrderOpenPrice() etc.) in indicators. If you converted your EA as indicator, then that kind of error would happen when trading functions gets executed. If your EA doesn't have any output buffers, then converting and running it as a strategy would probably help, before doing that mind to delete the previously compiled jfx file.