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: FuncGenerateId.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 GenerateId() function.
30 * @xsl.usage advanced
31 */
32public class FuncGenerateId extends FunctionDef1Arg
33{
34    static final long serialVersionUID = 973544842091724273L;
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 which = getArg0AsNode(xctxt);
48
49    if (DTM.NULL != which)
50    {
51      // Note that this is a different value than in previous releases
52      // of Xalan. It's sensitive to the exact encoding of the node
53      // handle anyway, so fighting to maintain backward compatability
54      // really didn't make sense; it may change again as we continue
55      // to experiment with balancing document and node numbers within
56      // that value.
57      return new XString("N" + Integer.toHexString(which).toUpperCase());
58    }
59    else
60      return XString.EMPTYSTRING;
61  }
62}
63