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 * 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
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 * distributed under the License is distributed on an "AS IS" BASIS,
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package com.sun.org.apache.xalan.internal.xsltc.dom;

import com.sun.org.apache.xalan.internal.xsltc.NodeIterator;
import com.sun.org.apache.xalan.internal.xsltc.runtime.BasisLibrary;

Author:
Jacek Ambroziak, Santiago Pericas-Geertsen, Morten Jorgensen/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 * @author Morten Jorgensen
 */
public abstract class NodeIteratorBase implements NodeIterator {

    
Cached computed value of last().
/**
     * Cached computed value of last().
     */
    protected int _last = -1;

    
Value of position() in this iterator. Incremented in
returnNode().
/**
     * Value of position() in this iterator. Incremented in
     * returnNode().
     */
    protected int _position = 0;

    
Store node in call to setMark().
/**
     * Store node in call to setMark().
     */
    protected int _markedNode;

    
Store node in call to setStartNode().
/**
     * Store node in call to setStartNode().
     */
    protected int _startNode = NodeIterator.END;

    
Flag indicating if "self" should be returned.
/**
     * Flag indicating if "self" should be returned.
     */
    protected boolean _includeSelf = false;

    
Flag indicating if iterator can be restarted.
/**
     * Flag indicating if iterator can be restarted.
     */
    protected boolean _isRestartable = true;

    
Setter for _isRestartable flag.
/**
     * Setter for _isRestartable flag.
     */
    public void setRestartable(boolean isRestartable) {
        _isRestartable = isRestartable;
    }

    
Initialize iterator using a node. If iterator is not
restartable, then do nothing. If node is equal to END then
subsequent calls to next() must return END.
/**
     * Initialize iterator using a node. If iterator is not
     * restartable, then do nothing. If node is equal to END then
     * subsequent calls to next() must return END.
     */
    abstract public NodeIterator setStartNode(int node);

    
Reset this iterator using state from last call to
setStartNode().
/**
     * Reset this iterator using state from last call to
     * setStartNode().
     */
    public NodeIterator reset() {
        final boolean temp = _isRestartable;
        _isRestartable = true;
        // Must adjust _startNode if self is included
        setStartNode(_includeSelf ? _startNode + 1 : _startNode);
        _isRestartable = temp;
        return this;
    }

    
Setter for _includeSelf flag.
/**
     * Setter for _includeSelf flag.
     */
    public NodeIterator includeSelf() {
        _includeSelf = true;
        return this;
    }

    
Default implementation of getLast(). Stores current position
and current node, resets the iterator, counts all nodes and
restores iterator to original state.
/**
     * Default implementation of getLast(). Stores current position
     * and current node, resets the iterator, counts all nodes and
     * restores iterator to original state.
     */
    public int getLast() {
        if (_last == -1) {
            final int temp = _position;
            setMark();
            reset();
            do {
                _last++;
            } while (next() != END);
            gotoMark();
            _position = temp;
        }
        return _last;
    }

    
Returns the position() in this iterator.
/**
     * Returns the position() in this iterator.
     */
    public int getPosition() {
        return _position == 0 ? 1 : _position;
    }

    
Indicates if position in this iterator is computed in reverse
document order. Note that nodes are always returned in document
order.
/**
     * Indicates if position in this iterator is computed in reverse
     * document order. Note that nodes are always returned in document
     * order.
     */
    public boolean isReverse() {
        return false;
    }

    
Clones and resets this iterator. Note that the cloned iterator is
not restartable. This is because cloning is needed for variable
references, and the context node of the original variable
declaration must be preserved.
/**
     * Clones and resets this iterator. Note that the cloned iterator is
     * not restartable. This is because cloning is needed for variable
     * references, and the context node of the original variable
     * declaration must be preserved.
     */
    public NodeIterator cloneIterator() {
        try {
            final NodeIteratorBase clone = (NodeIteratorBase)super.clone();
            clone._isRestartable = false;
            return clone.reset();
        }
        catch (CloneNotSupportedException e) {
            BasisLibrary.runTimeError(BasisLibrary.ITERATOR_CLONE_ERR,
                                      e.toString());
            return null;
        }
    }

    
Utility method that increments position and returns its
argument.
/**
     * Utility method that increments position and returns its
     * argument.
     */
    protected final int returnNode(final int node) {
        _position++;
        return node;
    }

    
Reset the position in this iterator.
/**
     * Reset the position in this iterator.
     */
    protected final NodeIterator resetPosition() {
        _position = 0;
        return this;
    }
}