gistfile1.txt

public class Main {

  @FunctionalInterface
  interface MagicalInterface<T> {
    void doSomething(T x);
  }

  static class Something {}

  static void vroomVroom(Something x) {
    System.out.println(x.toString());
  }

  public static void main(String[] args) {
    MagicalInterface var = (MagicalInterface<Something>) Main::vroomVroom;
    Object s = new Something();
    var.doSomething(s);
  }
}