Cloud.java

public class Cloud {

    public static void example(String s) {
        System.out.println("static mymethod " + s);
    }

    interface MyMethod{
        public void interfaceMethod(String s);
    }

    public static void main(String[] args) {
        new Heroku(Cloud::example);
    }

    static class Heroku {
        public Heroku(MyMethod m) {
            m.interfaceMethod("test string");
        }
    }
}