1 /*
   2  * Copyright (c) 2004, 2019, 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 org.xml.sax.ext;
  27 
  28 import java.io.IOException;
  29 import org.xml.sax.InputSource;
  30 import org.xml.sax.SAXException;
  31 import org.xml.sax.helpers.DefaultHandler;
  32 
  33 
  34 /**
  35  * This class extends the SAX2 base handler class to support the
  36  * SAX2 {@link LexicalHandler}, {@link DeclHandler}, and
  37  * {@link EntityResolver2} extensions.  Except for overriding the
  38  * original SAX1 {@link DefaultHandler#resolveEntity resolveEntity()}
  39  * method the added handler methods just return.  Subclassers may
  40  * override everything on a method-by-method basis.
  41  *
  42  * <p> <em>Note:</em> this class might yet learn that the
  43  * <em>ContentHandler.setDocumentLocator()</em> call might be passed a
  44  * {@link Locator2} object, and that the
  45  * <em>ContentHandler.startElement()</em> call might be passed a
  46  * {@link Attributes2} object.
  47  *
  48  * @since 1.5, SAX 2.0 (extensions 1.1 alpha)
  49  * @author David Brownell
  50  */
  51 public class DefaultHandler2 extends DefaultHandler
  52     implements LexicalHandler, DeclHandler, EntityResolver2
  53 {
  54     /** Constructs a handler which ignores all parsing events. */
  55     public DefaultHandler2 () { }
  56 
  57 
  58     // SAX2 ext-1.0 LexicalHandler
  59 
  60     public void startCDATA ()
  61     throws SAXException
  62         {}
  63 
  64     public void endCDATA ()
  65     throws SAXException
  66         {}
  67 
  68     public void startDTD (String name, String publicId, String systemId)
  69     throws SAXException
  70         {}
  71 
  72     public void endDTD ()
  73     throws SAXException
  74         {}
  75 
  76     public void startEntity (String name)
  77     throws SAXException
  78         {}
  79 
  80     public void endEntity (String name)
  81     throws SAXException
  82         {}
  83 
  84     public void comment (char ch [], int start, int length)
  85     throws SAXException
  86         { }
  87 
  88 
  89     // SAX2 ext-1.0 DeclHandler
  90 
  91     public void attributeDecl (String eName, String aName,
  92             String type, String mode, String value)
  93     throws SAXException
  94         {}
  95 
  96     public void elementDecl (String name, String model)
  97     throws SAXException
  98         {}
  99 
 100     public void externalEntityDecl (String name,
 101         String publicId, String systemId)
 102     throws SAXException
 103         {}
 104 
 105     public void internalEntityDecl (String name, String value)
 106     throws SAXException
 107         {}
 108 
 109     // SAX2 ext-1.1 EntityResolver2
 110 
 111     /**
 112      * Tells the parser that if no external subset has been declared
 113      * in the document text, none should be used.
 114      */
 115     public InputSource getExternalSubset (String name, String baseURI)
 116     throws SAXException, IOException
 117         { return null; }
 118 
 119     /**
 120      * Tells the parser to resolve the systemId against the baseURI
 121      * and read the entity text from that resulting absolute URI.
 122      * Note that because the older
 123      * {@link DefaultHandler#resolveEntity DefaultHandler.resolveEntity()},
 124      * method is overridden to call this one, this method may sometimes
 125      * be invoked with null <em>name</em> and <em>baseURI</em>, and
 126      * with the <em>systemId</em> already absolutized.
 127      */
 128     public InputSource resolveEntity (String name, String publicId,
 129             String baseURI, String systemId)
 130     throws SAXException, IOException
 131         { return null; }
 132 
 133     // SAX1 EntityResolver
 134 
 135     /**
 136      * Invokes
 137      * {@link EntityResolver2#resolveEntity EntityResolver2.resolveEntity()}
 138      * with null entity name and base URI.
 139      * You only need to override that method to use this class.
 140      */
 141     public InputSource resolveEntity (String publicId, String systemId)
 142     throws SAXException, IOException
 143         { return resolveEntity (null, publicId, null, systemId); }
 144 }