Java tutorial
/* * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/HttpException.java,v 1.19 2004/09/30 18:53:20 olegk Exp $ * $Revision: 480424 $ * $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $ * * ==================================================================== * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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; import java.io.IOException; import java.io.PrintStream; import java.io.PrintWriter; import java.lang.reflect.Method; /** * Signals that an HTTP or HttpClient exception has occurred. * * @author Laura Werner * * @version $Revision: 480424 $ $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $ */ public class HttpException extends IOException { /** * Creates a new HttpException with a <tt>null</tt> detail message. */ public HttpException() { super(); this.cause = null; } /** * Creates a new HttpException with the specified detail message. * * @param message the exception detail message */ public HttpException(String message) { super(message); this.cause = null; } /** * Creates a new HttpException with the specified detail message and cause. * * @param message the exception detail message * @param cause the <tt>Throwable</tt> that caused this exception, or <tt>null</tt> * if the cause is unavailable, unknown, or not a <tt>Throwable</tt> * * @since 3.0 */ public HttpException(String message, Throwable cause) { super(message); this.cause = cause; // If we're running on JDK 1.4 or later, tell Throwable what the cause was try { Class[] paramsClasses = new Class[] { Throwable.class }; Method initCause = Throwable.class.getMethod("initCause", paramsClasses); initCause.invoke(this, new Object[] { cause }); } catch (Exception e) { // The setCause method must not be available } } /** * Return the <tt>Throwable</tt> that caused this exception, or <tt>null</tt> * if the cause is unavailable, unknown, or not a <tt>Throwable</tt>. * * @return the <tt>Throwable</tt> that caused this exception, or <tt>null</tt> * if the cause is unavailable, unknown, or not a <tt>Throwable</tt> * * @since 3.0 */ public Throwable getCause() { return cause; } /** * Print this HttpException and its stack trace to the standard error stream. * * @since 3.0 */ public void printStackTrace() { printStackTrace(System.err); } /** * Print this HttpException and its stack trace to the specified print stream. * * @param s the <tt>PrintStream</tt> to which the exception and its stack trace * should be written * * @since 3.0 */ public void printStackTrace(PrintStream s) { try { // JDK 1.4 has a nice printStackTrace method that prints the cause's stack // trace too and prunes out duplicate stack frames. Call it if possible, // which is determined by checking whether JDK 1.4's getStackTrace method is present Class[] paramsClasses = new Class[] {}; this.getClass().getMethod("getStackTrace", paramsClasses); super.printStackTrace(s); } catch (Exception ex) { // If that didn't work, print it out ourselves // First print this exception's stack trace. super.printStackTrace(s); if (cause != null) { // Print out the exception that caused this one. // This will recurse if the cause is another HttpException. s.print("Caused by: "); cause.printStackTrace(s); } } } /** * Print this HttpException and its stack trace to the specified print writer. * * @param s the <tt>PrintWriter</tt> to which the exception and its stack trace * should be written * * @since 3.0 */ public void printStackTrace(PrintWriter s) { try { // JDK 1.4 has a nice printStackTrace method that prints the cause's stack // trace too and prunes out duplicate stack frames. Call it if possible, // which is determined by checking whether JDK 1.4's getStackTrace method is present Class[] paramsClasses = new Class[] {}; this.getClass().getMethod("getStackTrace", paramsClasses); super.printStackTrace(s); } catch (Exception ex) { // If that didn't work, print it out ourselves // First print this exception's stack trace. super.printStackTrace(s); if (cause != null) { // Print out the exception that caused this one. // This will recurse if the cause is another HttpException. s.print("Caused by: "); cause.printStackTrace(s); } } } /** * Sets the text description of the reason for an exception. * * @param reason The reason for the exception. * * @deprecated HttpClient no longer uses this for itself. It is only * provided for compatibility with existing clients, and will be removed * in a future release. */ public void setReason(String reason) { this.reason = reason; } /** * Get the text description of the reason for an exception. * * @deprecated HttpClient no longer uses this for itself. It is only * provided for compatibility with existing clients, and will be removed * in a future release. */ public String getReason() { return reason; } /** * Sets the status code description of the reason for an exception. * * @param code The reason for the exception. This is intended to be an * HTTP status code. * * @deprecated HttpClient no longer uses this for itself. It is only * provided for compatibility with existing clients, and will be removed * in a future release. */ public void setReasonCode(int code) { reasonCode = code; } /** * Get the status code description of the reason for an exception. * * @deprecated HttpClient no longer uses this for itself. It is only * provided for compatibility with existing clients, and will be removed * in a future release. */ public int getReasonCode() { return this.reasonCode; } /** * A "reason" string provided for compatibility with older clients. * * @deprecated HttpClient no longer uses this field for itself. It * is only provided for compatibility with existing clients. */ private String reason; /** * Reason code for compatibility with older clients. * * @deprecated HttpClient no longer uses this field for itself. * It is only provided for compatibility with existing clients. */ private int reasonCode = HttpStatus.SC_OK; /** The original Throwable representing the cause of this error */ private final Throwable cause; }