1/*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5/*
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements.  See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License.  You may obtain a copy of the License at
12 *
13 *      http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 */
21
22package com.sun.org.apache.xpath.internal.functions;
23
24import com.sun.org.apache.xml.internal.dtm.DTM;
25import com.sun.org.apache.xpath.internal.XPathContext;
26import com.sun.org.apache.xpath.internal.objects.XBoolean;
27import com.sun.org.apache.xpath.internal.objects.XObject;
28
29/**
30 * Execute the Lang() function.
31 * @xsl.usage advanced
32 */
33public class FuncLang extends FunctionOneArg
34{
35    static final long serialVersionUID = -7868705139354872185L;
36
37  /**
38   * Execute the function.  The function must return
39   * a valid object.
40   * @param xctxt The current execution context.
41   * @return A valid XObject.
42   *
43   * @throws javax.xml.transform.TransformerException
44   */
45  public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
46  {
47
48    String lang = m_arg0.execute(xctxt).str();
49    int parent = xctxt.getCurrentNode();
50    boolean isLang = false;
51    DTM dtm = xctxt.getDTM(parent);
52
53    while (DTM.NULL != parent)
54    {
55      if (DTM.ELEMENT_NODE == dtm.getNodeType(parent))
56      {
57        int langAttr = dtm.getAttributeNode(parent, "http://www.w3.org/XML/1998/namespace", "lang");
58
59        if (DTM.NULL != langAttr)
60        {
61          String langVal = dtm.getNodeValue(langAttr);
62          // %OPT%
63          if (langVal.toLowerCase().startsWith(lang.toLowerCase()))
64          {
65            int valLen = lang.length();
66
67            if ((langVal.length() == valLen)
68                    || (langVal.charAt(valLen) == '-'))
69            {
70              isLang = true;
71            }
72          }
73
74          break;
75        }
76      }
77
78      parent = dtm.getParent(parent);
79    }
80
81    return isLang ? XBoolean.S_TRUE : XBoolean.S_FALSE;
82  }
83}
84