Here you can find the source of countSubstring(String string, String substring)
private static int countSubstring(String string, String substring)
//package com.java2s; /*/*from w ww. j a v a 2s . c om*/ * Copyright (c) 2010 The Regents of the University of California. * All rights reserved. * * '$Author: welker $' * '$Date: 2010-05-05 22:21:26 -0700 (Wed, 05 May 2010) $' * '$Revision: 24234 $' * * Permission is hereby granted, without written agreement and without * license or royalty fees, to use, copy, modify, and distribute this * software and its documentation for any purpose, provided that the above * copyright notice and the following two paragraphs appear in all copies * of this software. * * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY * FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF * THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE * PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF * CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, * ENHANCEMENTS, OR MODIFICATIONS. * */ public class Main { private static int countSubstring(String string, String substring) { int searchFrom = -1; int count = 0; do { searchFrom = string.indexOf(substring, searchFrom + 1); if (searchFrom != -1) { count++; } } while (searchFrom != -1); return count; } }