1 /*
   2  * reserved comment block
   3  * DO NOT REMOVE OR ALTER!
   4  */
   5 /*
   6  * Copyright 2001-2004 The Apache Software Foundation.
   7  *
   8  * Licensed under the Apache License, Version 2.0 (the "License");
   9  * you may not use this file except in compliance with the License.
  10  * You may obtain a copy of the License at
  11  *
  12  *     http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20 /*
  21  * $Id: SingletonIterator.java,v 1.2.4.1 2005/09/06 10:15:18 pvedula Exp $
  22  */
  23 
  24 package com.sun.org.apache.xalan.internal.xsltc.dom;
  25 
  26 import com.sun.org.apache.xml.internal.dtm.DTMAxisIterator;
  27 import com.sun.org.apache.xml.internal.dtm.ref.DTMAxisIteratorBase;
  28 
  29 /**
  30  * @author Jacek Ambroziak
  31  * @author Santiago Pericas-Geertsen
  32  */
  33 public class SingletonIterator extends DTMAxisIteratorBase {
  34     private int _node;
  35     private final boolean _isConstant;
  36 
  37     public SingletonIterator() {
  38         this(Integer.MIN_VALUE, false);
  39     }
  40 
  41     public SingletonIterator(int node) {
  42         this(node, false);
  43     }
  44 
  45     public SingletonIterator(int node, boolean constant) {
  46         _node = _startNode = node;
  47         _isConstant = constant;
  48     }
  49 
  50     /**
  51      * Override the value of <tt>_node</tt> only when this
  52      * object was constructed using the empty constructor.
  53      */
  54     public DTMAxisIterator setStartNode(int node) {
  55         if (_isConstant) {
  56             _node = _startNode;
  57             return resetPosition();
  58         }
  59         else if (_isRestartable) {
  60             if (_node <= 0)
  61                 _node = _startNode = node;
  62             return resetPosition();
  63         }
  64         return this;
  65     }
  66 
  67     public DTMAxisIterator reset() {
  68         if (_isConstant) {
  69             _node = _startNode;
  70             return resetPosition();
  71         }
  72         else {
  73             final boolean temp = _isRestartable;
  74             _isRestartable = true;
  75             setStartNode(_startNode);
  76             _isRestartable = temp;
  77         }
  78         return this;
  79     }
  80 
  81     public int next() {
  82         final int result = _node;
  83         _node = DTMAxisIterator.END;
  84         return returnNode(result);
  85     }
  86 
  87     public void setMark() {
  88         _markedNode = _node;
  89     }
  90 
  91     public void gotoMark() {
  92         _node = _markedNode;
  93     }
  94 }