Here you can find the source of not(BitSet bitSets)
public static BitSet not(BitSet bitSets)
//package com.java2s; //License from project: Apache License import java.util.BitSet; public class Main { public static BitSet not(BitSet bitSets) { bitSets.flip(0, bitSets.size()); return bitSets; }//from ww w .j a va 2 s .c o m }