1 /*

     2  * reserved comment block

     3  * DO NOT REMOVE OR ALTER!

     4  */

     5 /*

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

     7  * contributor license agreements.  See the NOTICE file distributed with

     8  * this work for additional information regarding copyright ownership.

     9  * The ASF licenses this file to You under the Apache License, Version 2.0

    10  * (the "License"); you may not use this file except in compliance with

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

    12  *

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

    14  *

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

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

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

    18  * See the License for the specific language governing permissions and

    19  * limitations under the License.

    20  */

    21 

    22 package com.sun.org.apache.xpath.internal.axes;

    23 

    24 import com.sun.org.apache.xml.internal.dtm.DTM;

    25 import com.sun.org.apache.xml.internal.dtm.DTMFilter;

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

    27 import com.sun.org.apache.xpath.internal.compiler.Compiler;

    28 

    29 /**

    30  * This class implements an optimized iterator for

    31  * "node()" patterns, that is, any children of the

    32  * context node.

    33  * @see com.sun.org.apache.xpath.internal.axes.LocPathIterator

    34  * @xsl.usage advanced

    35  */

    36 public class ChildIterator extends LocPathIterator

    37 {

    38     static final long serialVersionUID = -6935428015142993583L;

    39 

    40   /**

    41    * Create a ChildIterator object.

    42    *

    43    * @param compiler A reference to the Compiler that contains the op map.

    44    * @param opPos The position within the op map, which contains the

    45    * location path expression for this itterator.

    46    * @param analysis Analysis bits of the entire pattern.

    47    *

    48    * @throws javax.xml.transform.TransformerException

    49    */

    50   ChildIterator(Compiler compiler, int opPos, int analysis)

    51           throws javax.xml.transform.TransformerException

    52   {

    53     super(compiler, opPos, analysis, false);

    54 

    55     // This iterator matches all kinds of nodes

    56     initNodeTest(DTMFilter.SHOW_ALL);

    57   }

    58 

    59   /**

    60    * Return the first node out of the nodeset, if this expression is

    61    * a nodeset expression.  This is the default implementation for

    62    * nodesets.

    63    * <p>WARNING: Do not mutate this class from this function!</p>

    64    * @param xctxt The XPath runtime context.

    65    * @return the first node out of the nodeset, or DTM.NULL.

    66    */

    67   public int asNode(XPathContext xctxt)

    68     throws javax.xml.transform.TransformerException

    69   {

    70     int current = xctxt.getCurrentNode();

    71 

    72     DTM dtm = xctxt.getDTM(current);

    73 

    74     return dtm.getFirstChild(current);

    75   }

    76 

    77   /**

    78    *  Returns the next node in the set and advances the position of the

    79    * iterator in the set. After a NodeIterator is created, the first call

    80    * to nextNode() returns the first node in the set.

    81    *

    82    * @return  The next <code>Node</code> in the set being iterated over, or

    83    *   <code>null</code> if there are no more members in that set.

    84    */

    85   public int nextNode()

    86   {

    87         if(m_foundLast)

    88                 return DTM.NULL;

    89 

    90     int next;

    91 

    92     m_lastFetched = next = (DTM.NULL == m_lastFetched)

    93                            ? m_cdtm.getFirstChild(m_context)

    94                            : m_cdtm.getNextSibling(m_lastFetched);

    95 

    96     // m_lastFetched = next;

    97     if (DTM.NULL != next)

    98     {

    99       m_pos++;

   100       return next;

   101     }

   102     else

   103     {

   104       m_foundLast = true;

   105 

   106       return DTM.NULL;

   107     }

   108   }

   109 

   110   /**

   111    * Returns the axis being iterated, if it is known.

   112    *

   113    * @return Axis.CHILD, etc., or -1 if the axis is not known or is of multiple

   114    * types.

   115    */

   116   public int getAxis()

   117   {

   118     return com.sun.org.apache.xml.internal.dtm.Axis.CHILD;

   119   }

   120 

   121 

   122 }