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<FONT color="green">001</FONT> /*<a name="line.1"></a>
<FONT color="green">002</FONT> * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<FONT color="green">003</FONT> * or more contributor license agreements. See the NOTICE file<a name="line.3"></a>
<FONT color="green">004</FONT> * distributed with this work for additional information<a name="line.4"></a>
<FONT color="green">005</FONT> * regarding copyright ownership. The ASF licenses this file<a name="line.5"></a>
<FONT color="green">006</FONT> * to you under the Apache License, Version 2.0 (the "License");<a name="line.6"></a>
<FONT color="green">007</FONT> * you may not use this file except in compliance with the License.<a name="line.7"></a>
<FONT color="green">008</FONT> * You may obtain a copy of the License at<a name="line.8"></a>
<FONT color="green">009</FONT> *<a name="line.9"></a>
<FONT color="green">010</FONT> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<FONT color="green">011</FONT> *<a name="line.11"></a>
<FONT color="green">012</FONT> * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
<FONT color="green">013</FONT> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
<FONT color="green">014</FONT> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
<FONT color="green">015</FONT> * See the License for the specific language governing permissions and<a name="line.15"></a>
<FONT color="green">016</FONT> * limitations under the License.<a name="line.16"></a>
<FONT color="green">017</FONT> */<a name="line.17"></a>
<FONT color="green">018</FONT> /*<a name="line.18"></a>
<FONT color="green">019</FONT> * $Id: FuncPosition.java 468655 2006-10-28 07:12:06Z minchau $<a name="line.19"></a>
<FONT color="green">020</FONT> */<a name="line.20"></a>
<FONT color="green">021</FONT> package org.apache.xpath.functions;<a name="line.21"></a>
<FONT color="green">022</FONT> <a name="line.22"></a>
<FONT color="green">023</FONT> import org.apache.xml.dtm.DTM;<a name="line.23"></a>
<FONT color="green">024</FONT> import org.apache.xml.dtm.DTMIterator;<a name="line.24"></a>
<FONT color="green">025</FONT> import org.apache.xpath.XPathContext;<a name="line.25"></a>
<FONT color="green">026</FONT> import org.apache.xpath.axes.SubContextList;<a name="line.26"></a>
<FONT color="green">027</FONT> import org.apache.xpath.compiler.Compiler;<a name="line.27"></a>
<FONT color="green">028</FONT> import org.apache.xpath.objects.XNumber;<a name="line.28"></a>
<FONT color="green">029</FONT> import org.apache.xpath.objects.XObject;<a name="line.29"></a>
<FONT color="green">030</FONT> <a name="line.30"></a>
<FONT color="green">031</FONT> /**<a name="line.31"></a>
<FONT color="green">032</FONT> * Execute the Position() function.<a name="line.32"></a>
<FONT color="green">033</FONT> * @xsl.usage advanced<a name="line.33"></a>
<FONT color="green">034</FONT> */<a name="line.34"></a>
<FONT color="green">035</FONT> public class FuncPosition extends Function<a name="line.35"></a>
<FONT color="green">036</FONT> {<a name="line.36"></a>
<FONT color="green">037</FONT> static final long serialVersionUID = -9092846348197271582L;<a name="line.37"></a>
<FONT color="green">038</FONT> private boolean m_isTopLevel;<a name="line.38"></a>
<FONT color="green">039</FONT> <a name="line.39"></a>
<FONT color="green">040</FONT> /**<a name="line.40"></a>
<FONT color="green">041</FONT> * Figure out if we're executing a toplevel expression.<a name="line.41"></a>
<FONT color="green">042</FONT> * If so, we can't be inside of a predicate. <a name="line.42"></a>
<FONT color="green">043</FONT> */<a name="line.43"></a>
<FONT color="green">044</FONT> public void postCompileStep(Compiler compiler)<a name="line.44"></a>
<FONT color="green">045</FONT> {<a name="line.45"></a>
<FONT color="green">046</FONT> m_isTopLevel = compiler.getLocationPathDepth() == -1;<a name="line.46"></a>
<FONT color="green">047</FONT> }<a name="line.47"></a>
<FONT color="green">048</FONT> <a name="line.48"></a>
<FONT color="green">049</FONT> /**<a name="line.49"></a>
<FONT color="green">050</FONT> * Get the position in the current context node list.<a name="line.50"></a>
<FONT color="green">051</FONT> *<a name="line.51"></a>
<FONT color="green">052</FONT> * @param xctxt Runtime XPath context.<a name="line.52"></a>
<FONT color="green">053</FONT> *<a name="line.53"></a>
<FONT color="green">054</FONT> * @return The current position of the itteration in the context node list, <a name="line.54"></a>
<FONT color="green">055</FONT> * or -1 if there is no active context node list.<a name="line.55"></a>
<FONT color="green">056</FONT> */<a name="line.56"></a>
<FONT color="green">057</FONT> public int getPositionInContextNodeList(XPathContext xctxt)<a name="line.57"></a>
<FONT color="green">058</FONT> {<a name="line.58"></a>
<FONT color="green">059</FONT> <a name="line.59"></a>
<FONT color="green">060</FONT> // System.out.println("FuncPosition- entry");<a name="line.60"></a>
<FONT color="green">061</FONT> // If we're in a predicate, then this will return non-null.<a name="line.61"></a>
<FONT color="green">062</FONT> SubContextList iter = m_isTopLevel ? null : xctxt.getSubContextList();<a name="line.62"></a>
<FONT color="green">063</FONT> <a name="line.63"></a>
<FONT color="green">064</FONT> if (null != iter)<a name="line.64"></a>
<FONT color="green">065</FONT> {<a name="line.65"></a>
<FONT color="green">066</FONT> int prox = iter.getProximityPosition(xctxt);<a name="line.66"></a>
<FONT color="green">067</FONT> <a name="line.67"></a>
<FONT color="green">068</FONT> // System.out.println("FuncPosition- prox: "+prox);<a name="line.68"></a>
<FONT color="green">069</FONT> return prox;<a name="line.69"></a>
<FONT color="green">070</FONT> }<a name="line.70"></a>
<FONT color="green">071</FONT> <a name="line.71"></a>
<FONT color="green">072</FONT> DTMIterator cnl = xctxt.getContextNodeList();<a name="line.72"></a>
<FONT color="green">073</FONT> <a name="line.73"></a>
<FONT color="green">074</FONT> if (null != cnl)<a name="line.74"></a>
<FONT color="green">075</FONT> {<a name="line.75"></a>
<FONT color="green">076</FONT> int n = cnl.getCurrentNode();<a name="line.76"></a>
<FONT color="green">077</FONT> if(n == DTM.NULL)<a name="line.77"></a>
<FONT color="green">078</FONT> {<a name="line.78"></a>
<FONT color="green">079</FONT> if(cnl.getCurrentPos() == 0)<a name="line.79"></a>
<FONT color="green">080</FONT> return 0;<a name="line.80"></a>
<FONT color="green">081</FONT> <a name="line.81"></a>
<FONT color="green">082</FONT> // Then I think we're in a sort. See sort21.xsl. So the iterator has <a name="line.82"></a>
<FONT color="green">083</FONT> // already been spent, and is not on the node we're processing. <a name="line.83"></a>
<FONT color="green">084</FONT> // It's highly possible that this is an issue for other context-list <a name="line.84"></a>
<FONT color="green">085</FONT> // functions. Shouldn't be a problem for last(), and it shouldn't be <a name="line.85"></a>
<FONT color="green">086</FONT> // a problem for current().<a name="line.86"></a>
<FONT color="green">087</FONT> try <a name="line.87"></a>
<FONT color="green">088</FONT> { <a name="line.88"></a>
<FONT color="green">089</FONT> cnl = cnl.cloneWithReset(); <a name="line.89"></a>
<FONT color="green">090</FONT> }<a name="line.90"></a>
<FONT color="green">091</FONT> catch(CloneNotSupportedException cnse)<a name="line.91"></a>
<FONT color="green">092</FONT> {<a name="line.92"></a>
<FONT color="green">093</FONT> throw new org.apache.xml.utils.WrappedRuntimeException(cnse);<a name="line.93"></a>
<FONT color="green">094</FONT> }<a name="line.94"></a>
<FONT color="green">095</FONT> int currentNode = xctxt.getContextNode();<a name="line.95"></a>
<FONT color="green">096</FONT> // System.out.println("currentNode: "+currentNode);<a name="line.96"></a>
<FONT color="green">097</FONT> while(DTM.NULL != (n = cnl.nextNode()))<a name="line.97"></a>
<FONT color="green">098</FONT> {<a name="line.98"></a>
<FONT color="green">099</FONT> if(n == currentNode)<a name="line.99"></a>
<FONT color="green">100</FONT> break;<a name="line.100"></a>
<FONT color="green">101</FONT> }<a name="line.101"></a>
<FONT color="green">102</FONT> }<a name="line.102"></a>
<FONT color="green">103</FONT> // System.out.println("n: "+n);<a name="line.103"></a>
<FONT color="green">104</FONT> // System.out.println("FuncPosition- cnl.getCurrentPos(): "+cnl.getCurrentPos());<a name="line.104"></a>
<FONT color="green">105</FONT> return cnl.getCurrentPos();<a name="line.105"></a>
<FONT color="green">106</FONT> }<a name="line.106"></a>
<FONT color="green">107</FONT> <a name="line.107"></a>
<FONT color="green">108</FONT> // System.out.println("FuncPosition - out of guesses: -1");<a name="line.108"></a>
<FONT color="green">109</FONT> return -1;<a name="line.109"></a>
<FONT color="green">110</FONT> }<a name="line.110"></a>
<FONT color="green">111</FONT> <a name="line.111"></a>
<FONT color="green">112</FONT> /**<a name="line.112"></a>
<FONT color="green">113</FONT> * Execute the function. The function must return<a name="line.113"></a>
<FONT color="green">114</FONT> * a valid object.<a name="line.114"></a>
<FONT color="green">115</FONT> * @param xctxt The current execution context.<a name="line.115"></a>
<FONT color="green">116</FONT> * @return A valid XObject.<a name="line.116"></a>
<FONT color="green">117</FONT> *<a name="line.117"></a>
<FONT color="green">118</FONT> * @throws javax.xml.transform.TransformerException<a name="line.118"></a>
<FONT color="green">119</FONT> */<a name="line.119"></a>
<FONT color="green">120</FONT> public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException<a name="line.120"></a>
<FONT color="green">121</FONT> {<a name="line.121"></a>
<FONT color="green">122</FONT> double pos = (double) getPositionInContextNodeList(xctxt);<a name="line.122"></a>
<FONT color="green">123</FONT> <a name="line.123"></a>
<FONT color="green">124</FONT> return new XNumber(pos);<a name="line.124"></a>
<FONT color="green">125</FONT> }<a name="line.125"></a>
<FONT color="green">126</FONT> <a name="line.126"></a>
<FONT color="green">127</FONT> /**<a name="line.127"></a>
<FONT color="green">128</FONT> * No arguments to process, so this does nothing.<a name="line.128"></a>
<FONT color="green">129</FONT> */<a name="line.129"></a>
<FONT color="green">130</FONT> public void fixupVariables(java.util.Vector vars, int globalsSize)<a name="line.130"></a>
<FONT color="green">131</FONT> {<a name="line.131"></a>
<FONT color="green">132</FONT> // no-op<a name="line.132"></a>
<FONT color="green">133</FONT> }<a name="line.133"></a>
<FONT color="green">134</FONT> }<a name="line.134"></a>
</PRE>
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