1/*
2 * Copyright (c) 2000, 2005, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26// SAX error handler.
27// http://www.saxproject.org
28// No warranty; no copyright -- use this as you will.
29// $Id: ErrorHandler.java,v 1.2 2004/11/03 22:44:52 jsuttor Exp $
30
31package org.xml.sax;
32
33
34/**
35 * Basic interface for SAX error handlers.
36 *
37 * <blockquote>
38 * <em>This module, both source code and documentation, is in the
39 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
40 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
41 * for further information.
42 * </blockquote>
43 *
44 * <p>If a SAX application needs to implement customized error
45 * handling, it must implement this interface and then register an
46 * instance with the XML reader using the
47 * {@link org.xml.sax.XMLReader#setErrorHandler setErrorHandler}
48 * method.  The parser will then report all errors and warnings
49 * through this interface.</p>
50 *
51 * <p><strong>WARNING:</strong> If an application does <em>not</em>
52 * register an ErrorHandler, XML parsing errors will go unreported,
53 * except that <em>SAXParseException</em>s will be thrown for fatal errors.
54 * In order to detect validity errors, an ErrorHandler that does something
55 * with {@link #error error()} calls must be registered.</p>
56 *
57 * <p>For XML processing errors, a SAX driver must use this interface
58 * in preference to throwing an exception: it is up to the application
59 * to decide whether to throw an exception for different types of
60 * errors and warnings.  Note, however, that there is no requirement that
61 * the parser continue to report additional errors after a call to
62 * {@link #fatalError fatalError}.  In other words, a SAX driver class
63 * may throw an exception after reporting any fatalError.
64 * Also parsers may throw appropriate exceptions for non-XML errors.
65 * For example, {@link XMLReader#parse XMLReader.parse()} would throw
66 * an IOException for errors accessing entities or the document.</p>
67 *
68 * @since 1.4, SAX 1.0
69 * @author David Megginson
70 * @see org.xml.sax.XMLReader#setErrorHandler
71 * @see org.xml.sax.SAXParseException
72 */
73public interface ErrorHandler {
74
75
76    /**
77     * Receive notification of a warning.
78     *
79     * <p>SAX parsers will use this method to report conditions that
80     * are not errors or fatal errors as defined by the XML
81     * recommendation.  The default behaviour is to take no
82     * action.</p>
83     *
84     * <p>The SAX parser must continue to provide normal parsing events
85     * after invoking this method: it should still be possible for the
86     * application to process the document through to the end.</p>
87     *
88     * <p>Filters may use this method to report other, non-XML warnings
89     * as well.</p>
90     *
91     * @param exception The warning information encapsulated in a
92     *                  SAX parse exception.
93     * @exception org.xml.sax.SAXException Any SAX exception, possibly
94     *            wrapping another exception.
95     * @see org.xml.sax.SAXParseException
96     */
97    public abstract void warning (SAXParseException exception)
98        throws SAXException;
99
100
101    /**
102     * Receive notification of a recoverable error.
103     *
104     * <p>This corresponds to the definition of "error" in section 1.2
105     * of the W3C XML 1.0 Recommendation.  For example, a validating
106     * parser would use this callback to report the violation of a
107     * validity constraint.  The default behaviour is to take no
108     * action.</p>
109     *
110     * <p>The SAX parser must continue to provide normal parsing
111     * events after invoking this method: it should still be possible
112     * for the application to process the document through to the end.
113     * If the application cannot do so, then the parser should report
114     * a fatal error even if the XML recommendation does not require
115     * it to do so.</p>
116     *
117     * <p>Filters may use this method to report other, non-XML errors
118     * as well.</p>
119     *
120     * @param exception The error information encapsulated in a
121     *                  SAX parse exception.
122     * @exception org.xml.sax.SAXException Any SAX exception, possibly
123     *            wrapping another exception.
124     * @see org.xml.sax.SAXParseException
125     */
126    public abstract void error (SAXParseException exception)
127        throws SAXException;
128
129
130    /**
131     * Receive notification of a non-recoverable error.
132     *
133     * <p><strong>There is an apparent contradiction between the
134     * documentation for this method and the documentation for {@link
135     * org.xml.sax.ContentHandler#endDocument}.  Until this ambiguity
136     * is resolved in a future major release, clients should make no
137     * assumptions about whether endDocument() will or will not be
138     * invoked when the parser has reported a fatalError() or thrown
139     * an exception.</strong></p>
140     *
141     * <p>This corresponds to the definition of "fatal error" in
142     * section 1.2 of the W3C XML 1.0 Recommendation.  For example, a
143     * parser would use this callback to report the violation of a
144     * well-formedness constraint.</p>
145     *
146     * <p>The application must assume that the document is unusable
147     * after the parser has invoked this method, and should continue
148     * (if at all) only for the sake of collecting additional error
149     * messages: in fact, SAX parsers are free to stop reporting any
150     * other events once this method has been invoked.</p>
151     *
152     * @param exception The error information encapsulated in a
153     *                  SAX parse exception.
154     * @exception org.xml.sax.SAXException Any SAX exception, possibly
155     *            wrapping another exception.
156     * @see org.xml.sax.SAXParseException
157     */
158    public abstract void fatalError (SAXParseException exception)
159        throws SAXException;
160
161}
162
163// end of ErrorHandler.java
164