Java tutorial
//package com.java2s; /** * Copyright 2000-2006 DFKI GmbH. * All Rights Reserved. Use is subject to license terms. * <p/> * This file is part of MARY TTS. * <p/> * MARY TTS is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, version 3 of the License. * <p/> * This program 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 Lesser General Public License for more details. * <p/> * You should have received a copy of the GNU Lesser General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ import java.io.File; public class Main { /** * Get the extension of a file. */ public static String getExtension(File f) { String ext = null; String s = f.getName(); int i = s.lastIndexOf('.'); if (i > 0 && i < s.length() - 1) { ext = s.substring(i + 1).toLowerCase(); } return ext; } }