java 8, Sort list of objects by attribute without custom comparator

Question

What is the cleanest short way to get this done ?

 class AnObject{
     Long  attr;
 }

 List list; 

I know it can be done

Answer 1

A null-safe option to JB Nizet's and Alex's answer above would be to do the following:

list.sort(Comparator.comparing(AnObject::getAttr, Comparator.nullsFirst(Comparator.naturalOrder())));

or

list.sort(Comparator.comparing(AnObject::getAttr, Comparator.nullsLast(Comparator.naturalOrder())));