Getting return list from forEach java 8

Question

I am trying to use a stream for something and I think I have a conceptual misunderstanding. I am trying to take an array, convert it to a stream, and .forEach item in the array I want to run a function and return a list of the results of that function from the foreach.

Essentially this:

Thing[] functionedThings = Array.stream(things).forEach(thing -> functionWithReturn(thing))

Is this possible? Am I using the wrong stream function?

Answer 1

You need map not forEach

List<Thing> functionedThings = Array.stream(things).map(thing -> functionWithReturn(thing)).collect(Collectors.toList());

Or toArray() on the stream directly if you want an array, like Holger said in the comments.