It appears that it's probably the `times` variable that is null, which means that every iteration of this `for` loop will fail. If that's the case I would just get rid of the try-catch and just check if `times` is null before entering the `for` loop.

If that's the case then you'd want to consider whether it's still an error if `times` is null, which would represent that there are no mean response times for that node.