001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 * 
010 *      http://www.apache.org/licenses/LICENSE-2.0
011 * 
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.oozie.util;
019
020import java.util.Enumeration;
021import java.net.URL;
022import java.net.URLDecoder;
023import java.io.IOException;
024
025/**
026 * Class utilities.
027 */
028public class ClassUtils {
029
030    /**
031     * Return the path to the JAR file in the classpath containing the specified class. <p/> This method has been
032     * canibalized from Hadoop's JobConf class.
033     *
034     * @param clazz class to find its JAR file.
035     * @return the JAR file of the class.
036     */
037    public static String findContainingJar(Class clazz) {
038        ClassLoader loader = clazz.getClassLoader();
039        String class_file = clazz.getName().replaceAll("\\.", "/") + ".class";
040        try {
041            for (Enumeration itr = loader.getResources(class_file); itr.hasMoreElements();) {
042                URL url = (URL) itr.nextElement();
043                if ("jar".equals(url.getProtocol())) {
044                    String toReturn = url.getPath();
045                    if (toReturn.startsWith("file:")) {
046                        toReturn = toReturn.substring("file:".length());
047                    }
048                    toReturn = URLDecoder.decode(toReturn, "UTF-8");
049                    return toReturn.replaceAll("!.*$", "");
050                }
051            }
052        }
053        catch (IOException e) {
054            throw new RuntimeException(e);
055        }
056        return null;
057    }
058
059}