[FIXED] Is it possible to save Java method in some Collections such as list?

Issue

I know that some language such as python can do this:

maps = []
cur = 1
maps.append(function)
for func in self.maps:
    cur = func(cur)

It adds a function to list and can iteratively call it. I'm wondering if Java can do the similar thing, if yes, how can it be done?

Solution

Yes. You can store a lambda in a list.

List<Function<Double, Double>> list = new ArrayList<>();
list.add(v->v*20);
list.add(v->v*30);

System.out.println(list.get(0).apply(10.));
System.out.println(list.get(1).apply(10.));

prints

200
300

Answered By - WJS
Answer Checked By - David Goodson (JavaFixing Volunteer)