001 /* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jcommon/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * ------------------
028 * FileUtilities.java
029 * ------------------
030 * (C) Copyright 2000-2004, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: FileUtilities.java,v 1.5 2005/10/18 13:16:02 mungady Exp $
036 *
037 * Changes (from 5-Nov-2001)
038 * -------------------------
039 * 05-Nov-2001 : Changed package to com.jrefinery.io.* (DG);
040 * 04-Mar-2002 : Renamed Files.java --> FileUtilities.java (DG);
041 * 10-Oct-2002 : Fixed errors reported by Checkstyle (DG);
042 *
043 */
044
045 package org.jfree.io;
046
047 import java.io.File;
048 import java.util.StringTokenizer;
049
050 /**
051 * A class containing useful utility methods relating to files.
052 *
053 * @author David Gilbert
054 */
055 public class FileUtilities {
056
057 /**
058 * To prevent unnecessary instantiation.
059 */
060 private FileUtilities() {
061 }
062
063 /**
064 * Returns a reference to a file with the specified name that is located
065 * somewhere on the classpath. The code for this method is an adaptation
066 * of code supplied by Dave Postill.
067 *
068 * @param name the filename.
069 *
070 * @return a reference to a file or <code>null</code> if no file could be found.
071 */
072 public static File findFileOnClassPath(final String name) {
073
074 final String classpath = System.getProperty("java.class.path");
075 final String pathSeparator = System.getProperty("path.separator");
076
077 final StringTokenizer tokenizer = new StringTokenizer(classpath, pathSeparator);
078
079 while (tokenizer.hasMoreTokens()) {
080 final String pathElement = tokenizer.nextToken();
081
082 final File directoryOrJar = new File(pathElement);
083 final File absoluteDirectoryOrJar = directoryOrJar.getAbsoluteFile();
084
085 if (absoluteDirectoryOrJar.isFile()) {
086 final File target = new File(absoluteDirectoryOrJar.getParent(), name);
087 if (target.exists()) {
088 return target;
089 }
090 }
091 else {
092 final File target = new File(directoryOrJar, name);
093 if (target.exists()) {
094 return target;
095 }
096 }
097
098 }
099 return null;
100
101 }
102
103 }