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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * 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

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

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package com.sun.org.apache.xpath.internal.functions;

import java.util.StringTokenizer;

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.StringVector;

import com.sun.org.apache.xpath.internal.NodeSetDTM;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.objects.XNodeSet;

import com.sun.org.apache.xpath.internal.objects.XObject;

import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;

/**

 * Execute the Id() function.

 * @xsl.usage advanced

 */

public class FuncId extends FunctionOneArg

{

    static final long serialVersionUID = 8930573966143567310L;

  /**

   * Fill in a list with nodes that match a space delimited list if ID

   * ID references.

   *

   * @param xctxt The runtime XPath context.

   * @param docContext The document where the nodes are being looked for.

   * @param refval A space delimited list of ID references.

   * @param usedrefs List of references for which nodes were found.

   * @param nodeSet Node set where the nodes will be added to.

   * @param mayBeMore true if there is another set of nodes to be looked for.

   *

   * @return The usedrefs value.

   */

  private StringVector getNodesByID(XPathContext xctxt, int docContext,

                                    String refval, StringVector usedrefs,

                                    NodeSetDTM nodeSet, boolean mayBeMore)

  {

    if (null != refval)

    {

      String ref = null;

//      DOMHelper dh = xctxt.getDOMHelper();

      StringTokenizer tokenizer = new StringTokenizer(refval);

      boolean hasMore = tokenizer.hasMoreTokens();

      DTM dtm = xctxt.getDTM(docContext);

      while (hasMore)

      {

        ref = tokenizer.nextToken();

        hasMore = tokenizer.hasMoreTokens();

        if ((null != usedrefs) && usedrefs.contains(ref))

        {

          ref = null;

          continue;

        }

        int node = dtm.getElementById(ref);

        if (DTM.NULL != node)

          nodeSet.addNodeInDocOrder(node, xctxt);

        if ((null != ref) && (hasMore || mayBeMore))

        {

          if (null == usedrefs)

            usedrefs = new StringVector();

          usedrefs.addElement(ref);

        }

      }

    }

    return usedrefs;

  }

  /**

   * 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

  {

    int context = xctxt.getCurrentNode();

    DTM dtm = xctxt.getDTM(context);

    int docContext = dtm.getDocument();

    if (DTM.NULL == docContext)

      error(xctxt, XPATHErrorResources.ER_CONTEXT_HAS_NO_OWNERDOC, null);

    XObject arg = m_arg0.execute(xctxt);

    int argType = arg.getType();

    XNodeSet nodes = new XNodeSet(xctxt.getDTMManager());

    NodeSetDTM nodeSet = nodes.mutableNodeset();

    if (XObject.CLASS_NODESET == argType)

    {

      DTMIterator ni = arg.iter();

      StringVector usedrefs = null;

      int pos = ni.nextNode();

      while (DTM.NULL != pos)

      {

        DTM ndtm = ni.getDTM(pos);

        String refval = ndtm.getStringValue(pos).toString();

        pos = ni.nextNode();

        usedrefs = getNodesByID(xctxt, docContext, refval, usedrefs, nodeSet,

                                DTM.NULL != pos);

      }

      // ni.detach();

    }

    else if (XObject.CLASS_NULL == argType)

    {

      return nodes;

    }

    else

    {

      String refval = arg.str();

      getNodesByID(xctxt, docContext, refval, null, nodeSet, false);

    }

    return nodes;

  }

}