Here you can find the source of equalsSet(Collection c1, Collection c2)
private static boolean equalsSet(Collection c1, Collection c2)
//package com.java2s; import java.util.*; public class Main { private static boolean equalsSet(Collection c1, Collection c2) { return new HashSet(c1).equals(new HashSet(c2)); }/*from www .j av a 2 s .c o m*/ }