How to convert Optional Double to Double in javafx

Question

The following code if compiled gives the following error. How to solve this

error: incompatible types: OptionalDouble cannot be converted to Double .average();

  Double todaypctpnl = openPositionsdata.stream()
                                     .mapToDouble(c->Double.parseDouble(c.getTodaypctpnl()))
                                     .average();

Answer 1

Did you take a look at the API docs for OptionalDouble?

There are several ways how to convert it back to a double value, like for example:

• double value = OptionalDouble.orElse(-1)
• double value = OptionalDouble.orElseThrow(IllegalStateException::new)

etc.

You will have to choose the one fitting best your current needs.

Answer 2

https://docs.oracle.com/javase/tutorial/collections/streams/reduction.html

Double todaypctpnl = openPositionsdata.stream() .mapToDouble(c->Double.parseDouble(c.getTodaypctpnl())) .average().getAsDouble();