code: /*
   * 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.
   */
  /*
   * $Id$
   */
  package org.apache.xpath.axes;
  
  import org.w3c.dom.Node;
  import org.w3c.dom.traversal.NodeIterator;
  
  /**
   * Classes who implement this interface can be a
   * <a href="http://www.w3.org/TR/xslt#dt-current-node-list">current node list</a>,
   * also refered to here as a <term>context node list</term>.
   * @xsl.usage advanced
   */
  public interface ContextNodeList
  {
  
    /**
     * Get the <a href="http://www.w3.org/TR/xslt#dt-current-node">current node</a>.
     *
     *
     * @return The current node, or null.
     */
    public Node getCurrentNode();
  
    /**
     * Get the current position, which is one less than
     * the next nextNode() call will retrieve.  i.e. if
     * you call getCurrentPos() and the return is 0, the next
     * fetch will take place at index 1.
     *
     * @return The position of the
     * <a href="http://www.w3.org/TR/xslt#dt-current-node">current node</a>
     * in the  <a href="http://www.w3.org/TR/xslt#dt-current-node-list">current node list</a>.
     */
    public int getCurrentPos();
  
    /**
     * Reset the iterator.
     */
    public void reset();
  
    /**
     * If setShouldCacheNodes(true) is called, then nodes will
     * be cached.  They are not cached by default.
     *
     * @param b true if the nodes should be cached.
     */
    public void setShouldCacheNodes(boolean b);
  
    /**
     * If an index is requested, NodeSetDTM will call this method
     * to run the iterator to the index.  By default this sets
     * m_next to the index.  If the index argument is -1, this
     * signals that the iterator should be run to the end.
     *
     * @param index The index to run to, or -1 if the iterator should be run
     *              to the end.
     */
    public void runTo(int index);
  
    /**
     * Set the current position in the node set.
     * @param i Must be a valid index.
     */
    public void setCurrentPos(int i);
  
    /**
     * Get the length of the list.
     *
     * @return The number of nodes in this node list.
     */
    public int size();
  
    /**
     * Tells if this NodeSetDTM is "fresh", in other words, if
     * the first nextNode() that is called will return the
     * first node in the set.
     *
     * @return true if the iteration of this list has not yet begun.
     */
    public boolean isFresh();
  
    /**
     * Get a cloned Iterator that is reset to the start of the iteration.
     *
     * @return A clone of this iteration that has been reset.
     *
     * @throws CloneNotSupportedException
     */
    public NodeIterator cloneWithReset() throws CloneNotSupportedException;
  
    /**
     * Get a clone of this iterator.  Be aware that this operation may be
     * somewhat expensive.
     *
     *
     * @return A clone of this object.
     *
     * @throws CloneNotSupportedException
     */
    public Object clone() throws CloneNotSupportedException;
  
    /**
     * Get the index of the last node in this list.
     *
     *
     * @return the index of the last node in this list.
     */
    public int getLast();
  
    /**
     * Set the index of the last node in this list.
     *
     *
     * @param last the index of the last node in this list.
     */
    public void setLast(int last);
  }
  