Here you can find the source of assertNotEmpty(String string, String exceptionMessageTitle)
public static void assertNotEmpty(String string, String exceptionMessageTitle)
//package com.java2s; //License from project: Open Source License public class Main { public static void assertNotEmpty(String string, String exceptionMessageTitle) { if (isNullOrEmpty(string)) { throw new IllegalArgumentException(exceptionMessageTitle + " cannot be null or empty string"); }// w w w . j a v a 2s . c om } public static boolean isNullOrEmpty(String string) { return string == null || string.length() == 0; } }