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 * Licensed to the Apache Software Foundation (ASF) under one or more
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 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
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 *      http://www.apache.org/licenses/LICENSE-2.0
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 * distributed under the License is distributed on an "AS IS" BASIS,
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package com.sun.org.apache.xpath.internal.functions;

import com.sun.org.apache.xml.internal.dtm.DTM;
import com.sun.org.apache.xml.internal.dtm.DTMIterator;
import com.sun.org.apache.xml.internal.utils.QName;
import com.sun.org.apache.xpath.internal.XPathContext;
import com.sun.org.apache.xpath.internal.axes.SubContextList;
import com.sun.org.apache.xpath.internal.compiler.Compiler;
import com.sun.org.apache.xpath.internal.objects.XNumber;
import com.sun.org.apache.xpath.internal.objects.XObject;
import java.util.List;

Execute the Position() function.
@xsl.usageadvanced
@LastModified: Oct 2017
/** * Execute the Position() function. * @xsl.usage advanced * @LastModified: Oct 2017 */
public class FuncPosition extends Function { static final long serialVersionUID = -9092846348197271582L; private boolean m_isTopLevel;
Figure out if we're executing a toplevel expression. If so, we can't be inside of a predicate.
/** * Figure out if we're executing a toplevel expression. * If so, we can't be inside of a predicate. */
public void postCompileStep(Compiler compiler) { m_isTopLevel = compiler.getLocationPathDepth() == -1; }
Get the position in the current context node list.
Params:
  • xctxt – Runtime XPath context.
Returns:The current position of the itteration in the context node list, or -1 if there is no active context node list.
/** * Get the position in the current context node list. * * @param xctxt Runtime XPath context. * * @return The current position of the itteration in the context node list, * or -1 if there is no active context node list. */
public int getPositionInContextNodeList(XPathContext xctxt) { // System.out.println("FuncPosition- entry"); // If we're in a predicate, then this will return non-null. SubContextList iter = m_isTopLevel ? null : xctxt.getSubContextList(); if (null != iter) { int prox = iter.getProximityPosition(xctxt); // System.out.println("FuncPosition- prox: "+prox); return prox; } DTMIterator cnl = xctxt.getContextNodeList(); if (null != cnl) { int n = cnl.getCurrentNode(); if(n == DTM.NULL) { if(cnl.getCurrentPos() == 0) return 0; // Then I think we're in a sort. See sort21.xsl. So the iterator has // already been spent, and is not on the node we're processing. // It's highly possible that this is an issue for other context-list // functions. Shouldn't be a problem for last(), and it shouldn't be // a problem for current(). try { cnl = cnl.cloneWithReset(); } catch(CloneNotSupportedException cnse) { throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(cnse); } int currentNode = xctxt.getContextNode(); // System.out.println("currentNode: "+currentNode); while(DTM.NULL != (n = cnl.nextNode())) { if(n == currentNode) break; } } // System.out.println("n: "+n); // System.out.println("FuncPosition- cnl.getCurrentPos(): "+cnl.getCurrentPos()); return cnl.getCurrentPos(); } // System.out.println("FuncPosition - out of guesses: -1"); return -1; }
Execute the function. The function must return a valid object.
Params:
  • xctxt – The current execution context.
Throws:
Returns:A valid XObject.
/** * Execute the function. The function must return * a valid object. * @param xctxt The current execution context. * @return A valid XObject. * * @throws javax.xml.transform.TransformerException */
public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException { double pos = (double) getPositionInContextNodeList(xctxt); return new XNumber(pos); }
No arguments to process, so this does nothing.
/** * No arguments to process, so this does nothing. */
public void fixupVariables(List<QName> vars, int globalsSize) { // no-op } }