Here you can find the source of isNotEmpty(final CharSequence cs)
public static boolean isNotEmpty(final CharSequence cs)
//package com.java2s; public class Main { public static boolean isNotEmpty(final CharSequence cs) { return !isEmpty(cs); }//ww w. java 2 s . co m public static boolean isEmpty(final CharSequence cs) { return cs == null || cs.length() == 0; } }