Example of using an anonymous comparator class

gistfile1.java

public List<Foo> sort(List<Foo> foos) {
  return Collections.sort(foos, new Comparator<Foo>() {
    @Override
    public int compare(Foo a, Foo b) {
      //comparison logic
    }
  });
}

gistfile2.java

public List<Foo> foosSortedByRange(List<Foo> foos, final Env env) {
  return Collections.sort(foos, new Comparator<Foo>() {
    @Override
    public int compare(Foo a, Foo b) {
      return a.range(env).compareTo(b.range(env));
    }
  });
}