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: TreeWalker2Result.java 468645 2006-10-28 06:57:24Z minchau $
20 */
21package org.apache.xalan.transformer;
22
23import org.apache.xalan.serialize.SerializerUtils;
24import org.apache.xml.dtm.DTM;
25import org.apache.xml.dtm.ref.DTMTreeWalker;
26import org.apache.xml.serializer.SerializationHandler;
27import org.apache.xpath.XPathContext;
28
29/**
30 * Handle a walk of a tree, but screen out attributes for
31 * the result tree.
32 * @xsl.usage internal
33 */
34public class TreeWalker2Result extends DTMTreeWalker
35{
36
37  /** The transformer instance          */
38  TransformerImpl m_transformer;
39
40  /** The result tree handler          */
41  SerializationHandler m_handler;
42
43  /** Node where to start the tree walk           */
44  int m_startNode;
45
46  /**
47   * Constructor.
48   *
49   * @param transformer Non-null transformer instance
50   * @param handler The Result tree handler to use
51   */
52  public TreeWalker2Result(TransformerImpl transformer,
53                           SerializationHandler handler)
54  {
55
56    super(handler, null);
57
58    m_transformer = transformer;
59    m_handler = handler;
60  }
61
62  /**
63   * Perform a pre-order traversal non-recursive style.
64   *
65   * @param pos Start node for traversal
66   *
67   * @throws TransformerException
68   */
69  public void traverse(int pos) throws org.xml.sax.SAXException
70  {
71    m_dtm = m_transformer.getXPathContext().getDTM(pos);
72    m_startNode = pos;
73
74    super.traverse(pos);
75  }
76
77        /**
78   * End processing of given node
79   *
80   *
81   * @param node Node we just finished processing
82   *
83   * @throws org.xml.sax.SAXException
84   */
85  protected void endNode(int node) throws org.xml.sax.SAXException
86  {
87    super.endNode(node);
88    if(DTM.ELEMENT_NODE == m_dtm.getNodeType(node))
89    {
90      m_transformer.getXPathContext().popCurrentNode();
91    }
92  }
93
94  /**
95   * Start traversal of the tree at the given node
96   *
97   *
98   * @param node Starting node for traversal
99   *
100   * @throws TransformerException
101   */
102  protected void startNode(int node) throws org.xml.sax.SAXException
103  {
104
105    XPathContext xcntxt = m_transformer.getXPathContext();
106    try
107    {
108
109      if (DTM.ELEMENT_NODE == m_dtm.getNodeType(node))
110      {
111        xcntxt.pushCurrentNode(node);
112
113        if(m_startNode != node)
114        {
115          super.startNode(node);
116        }
117        else
118        {
119          String elemName = m_dtm.getNodeName(node);
120          String localName = m_dtm.getLocalName(node);
121          String namespace = m_dtm.getNamespaceURI(node);
122
123          //xcntxt.pushCurrentNode(node);
124          // SAX-like call to allow adding attributes afterwards
125          m_handler.startElement(namespace, localName, elemName);
126          boolean hasNSDecls = false;
127          DTM dtm = m_dtm;
128          for (int ns = dtm.getFirstNamespaceNode(node, true);
129               DTM.NULL != ns; ns = dtm.getNextNamespaceNode(node, ns, true))
130          {
131            SerializerUtils.ensureNamespaceDeclDeclared(m_handler,dtm, ns);
132          }
133
134
135          for (int attr = dtm.getFirstAttribute(node);
136               DTM.NULL != attr; attr = dtm.getNextAttribute(attr))
137          {
138            SerializerUtils.addAttribute(m_handler, attr);
139          }
140        }
141
142      }
143      else
144      {
145        xcntxt.pushCurrentNode(node);
146        super.startNode(node);
147        xcntxt.popCurrentNode();
148      }
149    }
150    catch(javax.xml.transform.TransformerException te)
151    {
152      throw new org.xml.sax.SAXException(te);
153    }
154  }
155}
156