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 package javax.xml.transform;
  27 
  28 /**
  29  * <p>To provide customized error handling, implement this interface and
  30  * use the <code>setErrorListener</code> method to register an instance of the
  31  * implmentation with the {@link javax.xml.transform.Transformer}.  The
  32  * <code>Transformer</code> then reports all errors and warnings through this
  33  * interface.</p>
  34  *
  35  * <p>If an application does <em>not</em> register its own custom
  36  * <code>ErrorListener</code>, the default <code>ErrorListener</code>
  37  * is used which reports all warnings and errors to <code>System.err</code>
  38  * and does not throw any <code>Exception</code>s.
  39  * Applications are <em>strongly</em> encouraged to register and use
  40  * <code>ErrorListener</code>s that insure proper behavior for warnings and
  41  * errors.</p>
  42  *
  43  * <p>For transformation errors, a <code>Transformer</code> must use this
  44  * interface instead of throwing an <code>Exception</code>: it is up to the
  45  * application to decide whether to throw an <code>Exception</code> for
  46  * different types of errors and warnings.  Note however that the
  47  * <code>Transformer</code> is not required to continue with the transformation
  48  * after a call to {@link #fatalError(TransformerException exception)}.</p>
  49  *
  50  * <p><code>Transformer</code>s may use this mechanism to report XML parsing
  51  * errors as well as transformation errors.</p>
  52  */
  53 public interface ErrorListener {
  54 
  55     /**
  56      * Receive notification of a warning.
  57      *
  58      * <p>{@link javax.xml.transform.Transformer} can use this method to report
  59      * conditions that are not errors or fatal errors.  The default behaviour
  60      * is to take no action.</p>
  61      *
  62      * <p>After invoking this method, the Transformer must continue with
  63      * the transformation. It should still be possible for the
  64      * application to process the document through to the end.</p>
  65      *
  66      * @param exception The warning information encapsulated in a
  67      *                  transformer exception.
  68      *
  69      * @throws javax.xml.transform.TransformerException if the application
  70      * chooses to discontinue the transformation.
  71      *
  72      * @see javax.xml.transform.TransformerException
  73      */
  74     public abstract void warning(TransformerException exception)
  75         throws TransformerException;
  76 
  77     /**
  78      * Receive notification of a recoverable error.
  79      *
  80      * <p>The transformer must continue to try and provide normal transformation
  81      * after invoking this method.  It should still be possible for the
  82      * application to process the document through to the end if no other errors
  83      * are encountered.</p>
  84      *
  85      * @param exception The error information encapsulated in a
  86      *                  transformer exception.
  87      *
  88      * @throws javax.xml.transform.TransformerException if the application
  89      * chooses to discontinue the transformation.
  90      *
  91      * @see javax.xml.transform.TransformerException
  92      */
  93     public abstract void error(TransformerException exception)
  94         throws TransformerException;
  95 
  96     /**
  97      * <p>Receive notification of a non-recoverable error.</p>
  98      *
  99      * <p>The processor may choose to continue, but will not normally
 100      * proceed to a successful completion.</p>
 101      *
 102      * <p>The method should throw an exception if it is unable to
 103      * process the error, or if it wishes execution to terminate
 104      * immediately. The processor will not necessarily honor this
 105      * request.</p>
 106      *
 107      * @param exception The error information encapsulated in a
 108      *    <code>TransformerException</code>.
 109      *
 110      * @throws javax.xml.transform.TransformerException if the application
 111      * chooses to discontinue the transformation.
 112      *
 113      * @see javax.xml.transform.TransformerException
 114      */
 115     public abstract void fatalError(TransformerException exception)
 116         throws TransformerException;
 117 }