FuncNamespace.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: FuncNamespace.java 468655 2006-10-28 07:12:06Z minchau $
20 */
21package org.apache.xpath.functions;
22
23import org.apache.xml.dtm.DTM;
24import org.apache.xpath.XPathContext;
25import org.apache.xpath.objects.XObject;
26import org.apache.xpath.objects.XString;
27
28/**
29 * Execute the Namespace() function.
30 * @xsl.usage advanced
31 */
32public class FuncNamespace extends FunctionDef1Arg
33{
34    static final long serialVersionUID = -4695674566722321237L;
35
36  /**
37   * Execute the function.  The function must return
38   * a valid object.
39   * @param xctxt The current execution context.
40   * @return A valid XObject.
41   *
42   * @throws javax.xml.transform.TransformerException
43   */
44  public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
45  {
46
47    int context = getArg0AsNode(xctxt);
48
49    String s;
50    if(context != DTM.NULL)
51    {
52      DTM dtm = xctxt.getDTM(context);
53      int t = dtm.getNodeType(context);
54      if(t == DTM.ELEMENT_NODE)
55      {
56        s = dtm.getNamespaceURI(context);
57      }
58      else if(t == DTM.ATTRIBUTE_NODE)
59      {
60
61        // This function always returns an empty string for namespace nodes.
62        // We check for those here.  Fix inspired by Davanum Srinivas.
63
64        s = dtm.getNodeName(context);
65        if(s.startsWith("xmlns:") || s.equals("xmlns"))
66          return XString.EMPTYSTRING;
67
68        s = dtm.getNamespaceURI(context);
69      }
70      else
71        return XString.EMPTYSTRING;
72    }
73    else
74      return XString.EMPTYSTRING;
75
76    return ((null == s) ? XString.EMPTYSTRING : new XString(s));
77  }
78}
79