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: FuncCurrent.java 468655 2006-10-28 07:12:06Z minchau $
20  */
21 package org.apache.xpath.functions;
22 
23 import org.apache.xml.dtm.DTM;
24 import org.apache.xml.dtm.DTMIterator;
25 import org.apache.xpath.XPathContext;
26 import org.apache.xpath.axes.LocPathIterator;
27 import org.apache.xpath.axes.PredicatedNodeTest;
28 import org.apache.xpath.objects.XNodeSet;
29 import org.apache.xpath.objects.XObject;
30 import org.apache.xpath.axes.SubContextList;
31 import org.apache.xpath.patterns.StepPattern;
32 import org.apache.xalan.res.XSLMessages;
33 import org.apache.xalan.res.XSLTErrorResources;
34 
35 
36 /**
37  * Execute the current() function.
38  * @xsl.usage advanced
39  */
40 public class FuncCurrent extends Function
41 {
42     static final long serialVersionUID = 5715316804877715008L;
43 
44   /**
45    * Execute the function.  The function must return
46    * a valid object.
47    * @param xctxt The current execution context.
48    * @return A valid XObject.
49    *
50    * @throws javax.xml.transform.TransformerException
51    */
execute(XPathContext xctxt)52   public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException
53   {
54 
55     SubContextList subContextList = xctxt.getCurrentNodeList();
56     int currentNode = DTM.NULL;
57 
58     if (null != subContextList) {
59         if (subContextList instanceof PredicatedNodeTest) {
60             LocPathIterator iter = ((PredicatedNodeTest)subContextList)
61                                                           .getLocPathIterator();
62             currentNode = iter.getCurrentContextNode();
63          } else if(subContextList instanceof StepPattern) {
64            throw new RuntimeException(XSLMessages.createMessage(
65               XSLTErrorResources.ER_PROCESSOR_ERROR,null));
66          }
67     } else {
68         // not predicate => ContextNode == CurrentNode
69         currentNode = xctxt.getContextNode();
70     }
71     return new XNodeSet(currentNode, xctxt.getDTMManager());
72   }
73 
74   /**
75    * No arguments to process, so this does nothing.
76    */
fixupVariables(java.util.Vector vars, int globalsSize)77   public void fixupVariables(java.util.Vector vars, int globalsSize)
78   {
79     // no-op
80   }
81 
82 }
83