- /*
- * $Header: /home/cvs/jakarta-commons/httpclient/src/java/org/apache/commons/httpclient/util/ExceptionUtil.java,v 1.4 2004/05/13 04:01:22 mbecke Exp $
- * $Revision: 1.4 $
- * $Date: 2004/05/13 04:01:22 $
- *
- * ====================================================================
- *
- * Copyright 1999-2004 The Apache Software Foundation
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- *
- */
- package org.apache.commons.httpclient.util;
-
- import java.lang.reflect.Method;
-
- import org.apache.commons.logging.Log;
- import org.apache.commons.logging.LogFactory;
-
- /**
- * The home for utility methods that handle various exception-related tasks.
- *
- * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
- * @author <a href="mailto:laura@lwerner.org">Laura Werner</a>
- *
- * @since 3.0
- */
- public class ExceptionUtil {
-
- /** Log object for this class. */
- private static final Log LOG = LogFactory.getLog(ExceptionUtil.class);
-
- /** A reference to Throwable's initCause method, or null if it's not there in this JVM */
- static private final Method initCause = getInitCauseMethod();
-
- /**
- * Returns a <code>Method<code> allowing access to
- * {@link Throwable.initCause(Throwable) initCause} method of {@link Throwable},
- * or <code>null</code> if the method
- * does not exist.
- *
- * @return A <code>Method<code> for <code>Throwable.initCause</code>, or
- * <code>null</code> if unavailable.
- */
- static private Method getInitCauseMethod() {
- try {
- Class[] paramsClasses = new Class[] { Throwable.class };
- return Throwable.class.getMethod("initCause", paramsClasses);
- } catch (NoSuchMethodException e) {
- return null;
- }
- }
-
- /**
- * If we're running on JDK 1.4 or later, initialize the cause for the given throwable.
- *
- * @param throwable The throwable.
- * @param cause The cause of the throwable.
- */
- public static void initCause(Throwable throwable, Throwable cause) {
- if (initCause != null) {
- try {
- initCause.invoke(throwable, new Object[] { cause });
- } catch (Exception e) {
- LOG.warn("Exception invoking Throwable.initCause", e);
- }
- }
- }
- }