001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.activemq.web.util;
018
019public class ExceptionUtils {
020
021    /**
022     * Finds the root cause of an exception.  Will return the original
023     * exception if the first getCause returns null.
024     *
025     * @param e
026     * @return
027     */
028    public static Throwable getRootCause(final Throwable e) {
029        Throwable result = e;
030
031        //loop over to find the root cause while guarding against cycles
032        while(result != null && result.getCause() != null
033                && e != result.getCause() && result != result.getCause() ) {
034            result = result.getCause();
035        }
036
037        return result;
038    }
039
040    /**
041     * Returns true if the passed in class is the root cause of the exception
042     *
043     * @param e
044     * @param clazz
045     * @return
046     */
047    public static boolean isRootCause(final Throwable e, final Class<?> clazz) {
048        if (clazz == null || e == null) {
049            return false;
050        }
051        return clazz.isInstance(getRootCause(e));
052    }
053
054}