Here you can find the source of substitute(String s, String from, String to)
public static String substitute(String s, String from, String to)
//package com.java2s; /*// w w w.ja v a 2 s .com * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ public class Main { public static String substitute(String s, String from, String to) { if (s == null || from == null || s.equals("") || from.equals("")) { return s; } String res = ""; int ind = s.indexOf(from); while (ind >= 0) { res += s.substring(0, ind); res += to; s = s.substring(ind + 1); ind = s.indexOf(from); } res += s; return res; } }