How does Java 8 know which String::compareTo method reference to use when sorting?

Question

How does Java know which String::compareTo method reference to use when calling Collections.sort(someListOfStrings, String::compareTo);? comp

Answer 1

OK, the source of Collections.sort() looks as follows:

public static  void sort(List list, Comparator c) {
   Object[] a = list.toArray();
   Arrays.sort(a, (Comparator)c);
   ListIterator i = list.listIterator();
   for (int j=0; j

I think it is quite clear now. The contents is a list. It means it has an order and the items are treated one by one in that order.