Here you can find the source of substring(String self, Integer startIndex, Integer endIndex)
public static String substring(String self, Integer startIndex, Integer endIndex)
//package com.java2s; // Licensed under the Apache License, Version 2.0 (the "License"); public class Main { public static String substring(String self, Integer startIndex, Integer endIndex) {// ww w . j av a 2 s.c om return self.substring(startIndex, endIndex); } public static String substring(String self, Integer startIndex) { return self.substring(startIndex); } }