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/* * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ // SAX exception class. // http://www.saxproject.org // No warranty; no copyright -- use this as you will. // $Id: SAXException.java,v 1.3 2004/11/03 22:55:32 jsuttor Exp $ package org.xml.sax; import java.io.IOException; import java.io.InvalidClassException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.ObjectStreamField; /** * Encapsulate a general SAX error or warning. * * <blockquote> * <em>This module, both source code and documentation, is in the * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em> * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a> * for further information. * </blockquote> * * <p>This class can contain basic error or warning information from * either the XML parser or the application: a parser writer or * application writer can subclass it to provide additional * functionality. SAX handlers may throw this exception or * any exception subclassed from it.</p> * * <p>If the application needs to pass through other types of * exceptions, it must wrap those exceptions in a SAXException * or an exception derived from a SAXException.</p> * * <p>If the parser or application needs to include information about a * specific location in an XML document, it should use the * {@link org.xml.sax.SAXParseException SAXParseException} subclass.</p> * * @since 1.4, SAX 1.0 * @author David Megginson * @version 2.0.1 (sax2r2) * @see org.xml.sax.SAXParseException */ public class SAXException extends Exception { /** * Create a new SAXException. */ public SAXException() { super(); } /** * Create a new SAXException. * * @param message The error or warning message. */ public SAXException(String message) { super(message); } /** * Create a new SAXException wrapping an existing exception. * * <p>The existing exception will be embedded in the new * one, and its message will become the default message for * the SAXException.</p> * * @param e The exception to be wrapped in a SAXException. */ public SAXException(Exception e) { super(e); } /** * Create a new SAXException from an existing exception. * * <p>The existing exception will be embedded in the new * one, but the new exception will have its own message.</p> * * @param message The detail message. * @param e The exception to be wrapped in a SAXException. */ public SAXException(String message, Exception e) { super(message, e); } /** * Return a detail message for this exception. * * <p>If there is an embedded exception, and if the SAXException * has no detail message of its own, this method will return * the detail message from the embedded exception.</p> * * @return The error or warning message. */ public String getMessage() { String message = super.getMessage(); Throwable cause = super.getCause(); if (message == null && cause != null) { return cause.getMessage(); } else { return message; } } /** * Return the embedded exception, if any. * * @return The embedded exception, or null if there is none. */ public Exception getException() { return getExceptionInternal(); } /** * Return the cause of the exception * * @return Return the cause of the exception */ public Throwable getCause() { return super.getCause(); } /** * Override toString to pick up any embedded exception. * * @return A string representation of this exception. */ public String toString() { Throwable exception = super.getCause(); if (exception != null) { return super.toString() + "\n" + exception.toString(); } else { return super.toString(); } } ////////////////////////////////////////////////////////////////////// // Internal state. ////////////////////////////////////////////////////////////////////// private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("exception", Exception.class) }; /** * Writes "exception" field to the stream. * * @param out stream used for serialization. * @throws IOException thrown by <code>ObjectOutputStream</code> */ private void writeObject(ObjectOutputStream out) throws IOException { ObjectOutputStream.PutField fields = out.putFields(); fields.put("exception", getExceptionInternal()); out.writeFields(); } /** * Reads the "exception" field from the stream. * And initializes the "exception" if it wasn't * done before. * * @param in stream used for deserialization * @throws IOException thrown by <code>ObjectInputStream</code> * @throws ClassNotFoundException thrown by <code>ObjectInputStream</code> */ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { ObjectInputStream.GetField fields = in.readFields(); Exception exception = (Exception) fields.get("exception", null); Throwable superCause = super.getCause(); // if super.getCause() and 'exception' fields present then always use // getCause() value. Otherwise, use 'exception' to initialize cause if (superCause == null && exception != null) { try { super.initCause(exception); } catch (IllegalStateException e) { throw new InvalidClassException("Inconsistent state: two causes"); } } } // Internal method to guard against overriding of public getException // method by SAXException subclasses private Exception getExceptionInternal() { Throwable cause = super.getCause(); if (cause instanceof Exception) { return (Exception) cause; } else { return null; } } // Added serialVersionUID to preserve binary compatibility static final long serialVersionUID = 583241635256073760L; } // end of SAXException.java