Here you can find the source of isNotEmpty(Collection> list)
public static boolean isNotEmpty(Collection<?> list)
//package com.java2s; import java.util.Collection; public class Main { public static boolean isNotEmpty(Collection<?> list) { return !isEmpty(list); }//w ww . jav a2 s. co m public static boolean isEmpty(Collection<?> list) { if (list == null) { return true; } return list.isEmpty(); } }