Sorting on a potentially null field

nullFieldSort.md

Say I have a class with a potentially-null field and I want to sort a List of class instances on that field first (nulls last), then fall back on a second non-null field.

@Data
class Foo {
    String bar;
    int baz
}

Given a list of foos called foos and static imports from java.util.Comparator:

   foos.stream()
       .sorted(comparing(Foo::getBar, nullsLast(String::compareTo)).thenComparing(Foo::getBaz))