Call function passed as an argument with arguments

Question

I have a function, which takes a function and string as arguments, I want to call this function with the string argument and return the result.

Something like this:

public static String mainFunc(Callable func, String s) {
    return func.call(s); // Error
}

mainFunc(SomeObject::instanceMethod, s)

But as you can see it is not working. Please note that I don't necessarily need to use Callable, it can be any other interface.

What's the error message? – OneCricketeer Mar 19 '18 at 13:57 — OneCricketeer, Mar 19 '18 at 13:57
@Jarrod that duplicate is not what the question is asking. – Andy Turner Mar 19 '18 at 14:02 — Andy Turner, Mar 19 '18 at 14:02

Andy Turner · Accepted Answer · 2018-03-19T14:02:28.123

5

A Callable takes no parameters.

If it takes a String and returns a String, it's a Function<String, String> (or, more generally, a Function<? super String, ? extends String>).

public static String mainFunc(Function<String, String> func, String s) {
  return func.apply(s);
}

Although, there's not very much point in this method: just invoke func.apply directly.

edited Mar 19 '18 at 14:02

answered Mar 19 '18 at 13:57

Andy Turner

137,514
11
162
243

@cricket_007 thanks for the edit, but please take care not to stomp my edits. – Andy Turner Mar 19 '18 at 14:01
I don't think I can control that on mobile. Sorry – OneCricketeer Mar 19 '18 at 14:04
Worked like a charm. Thanks – Shota Mar 19 '18 at 14:04

Call function passed as an argument with arguments

1 Answers1