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     */
018    package org.apache.oozie.util;
019    
020    import java.util.Enumeration;
021    import java.net.URL;
022    import java.net.URLDecoder;
023    import java.io.IOException;
024    
025    /**
026     * Class utilities.
027     */
028    public 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    }