Java Lambda Expression Method reference find the maximum value in a collection

// Use a method reference to help find the maximum value in a collection. 
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

class My {/*  ww w.  j a  v a 2  s. co m*/
  private int val;

  My(int v) {
    val = v;
  }

  int getVal() {
    return val;
  }
}

public class Main {
  // A compare() method compatible with the one defined by Comparator<T>.
  static int compareMC(My a, My b) {
    return a.getVal() - b.getVal();
  }

  public static void main(String args[]) {
    List<My> al = new ArrayList<My>();

    al.add(new My(1));
    al.add(new My(4));
    al.add(new My(2));
    al.add(new My(9));
    al.add(new My(3));
    al.add(new My(7));

    // Find the maximum value in list using the compareMC() method.
    My maxValObj = Collections.max(al, Main::compareMC);

    System.out.println("Maximum value is: " + maxValObj.getVal());
  }
}