DOM2Helper.java revision 9f8118474e9513f7a5b7d2a05e4a0fb15d1a6569 
1/*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the  "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 *     http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18/*
19 * $Id: DOM2Helper.java 468654 2006-10-28 07:09:23Z minchau $
20 */
21package org.apache.xml.serializer.utils;
22
23import org.w3c.dom.Node;
24
25/**
26 * This class provides a DOM level 2 "helper", which provides services currently
27 * not provided be the DOM standard.
28 *
29 * This class is a copy of the one in org.apache.xml.utils.
30 * It exists to cut the serializers dependancy on that package.
31 *
32 * The differences from the original class are:
33 * it doesn't extend DOMHelper, not depricated,
34 * dropped method isNodeAfter(Node node1, Node node2)
35 * dropped method parse(InputSource)
36 * dropped method supportSAX()
37 * dropped method setDocument(doc)
38 * dropped method checkNode(Node)
39 * dropped method getDocument()
40 * dropped method getElementByID(String id, Document doc)
41 * dropped method getParentOfNode(Node node)
42 * dropped field Document m_doc;
43 * made class non-public
44 *
45 * This class is not a public API, it is only public because it is
46 * used in org.apache.xml.serializer.
47 *
48 * @xsl.usage internal
49 */
50public final class DOM2Helper
51{
52
53  /**
54   * Construct an instance.
55   */
56  public DOM2Helper(){}
57
58  /**
59   * Returns the local name of the given node, as defined by the
60   * XML Namespaces specification. This is prepared to handle documents
61   * built using DOM Level 1 methods by falling back upon explicitly
62   * parsing the node name.
63   *
64   * @param n Node to be examined
65   *
66   * @return String containing the local name, or null if the node
67   * was not assigned a Namespace.
68   */
69  public String getLocalNameOfNode(Node n)
70  {
71
72    String name = n.getLocalName();
73
74    return (null == name) ? getLocalNameOfNodeFallback(n) : name;
75  }
76
77  /**
78   * Returns the local name of the given node. If the node's name begins
79   * with a namespace prefix, this is the part after the colon; otherwise
80   * it's the full node name.
81   *
82   * This method is copied from org.apache.xml.utils.DOMHelper
83   *
84   * @param n the node to be examined.
85   *
86   * @return String containing the Local Name
87   */
88  private String getLocalNameOfNodeFallback(Node n)
89  {
90
91    String qname = n.getNodeName();
92    int index = qname.indexOf(':');
93
94    return (index < 0) ? qname : qname.substring(index + 1);
95  }
96
97  /**
98   * Returns the Namespace Name (Namespace URI) for the given node.
99   * In a Level 2 DOM, you can ask the node itself. Note, however, that
100   * doing so conflicts with our decision in getLocalNameOfNode not
101   * to trust the that the DOM was indeed created using the Level 2
102   * methods. If Level 1 methods were used, these two functions will
103   * disagree with each other.
104   * <p>
105   * TODO: Reconcile with getLocalNameOfNode.
106   *
107   * @param n Node to be examined
108   *
109   * @return String containing the Namespace URI bound to this DOM node
110   * at the time the Node was created.
111   */
112  public String getNamespaceOfNode(Node n)
113  {
114    return n.getNamespaceURI();
115  }
116
117  /** Field m_useDOM2getNamespaceURI is a compile-time flag which
118   *  gates some of the parser options used to build a DOM -- but
119   * that code is commented out at this time and nobody else
120   * references it, so I've commented this out as well. */
121  //private boolean m_useDOM2getNamespaceURI = false;
122}
123