Here you can find the source of assertNotEmpty(final String str)
public static boolean assertNotEmpty(final String str)
//package com.java2s; //License from project: Open Source License public class Main { public static boolean assertNotEmpty(final String str) { return null != str && !str.isEmpty(); }//ww w . jav a 2 s . com public static boolean isEmpty(final String value) { return null == value || value.isEmpty(); } }