content: /*
   * Copyright (c) 2004 World Wide Web Consortium,
   *
   * (Massachusetts Institute of Technology, European Research Consortium for
   * Informatics and Mathematics, Keio University). All Rights Reserved. This
   * work is distributed under the W3C(r) Software License [1] in the hope that
   * it will be useful, but WITHOUT ANY WARRANTY; without even the implied
   * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   *
   * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
   */
  
  package mf.org.w3c.dom.xpath;
  
  import mf.org.w3c.dom.DOMException;
  import mf.org.w3c.dom.Node;
  
  /**
   * The <code>XPathResult</code> interface represents the result of the
   * evaluation of an XPath 1.0 expression within the context of a particular
   * node. Since evaluation of an XPath expression can result in various
   * result types, this object makes it possible to discover and manipulate
   * the type and value of the result.
   * <p>See also the <a href='http://www.w3.org/TR/2004/NOTE-DOM-Level-3-XPath-20040226'>Document Object Model (DOM) Level 3 XPath Specification</a>.
   */
  public interface XPathResult {
      // XPathResultType
      /**
       * This code does not represent a specific type. An evaluation of an XPath
       * expression will never produce this type. If this type is requested,
       * then the evaluation returns whatever type naturally results from
       * evaluation of the expression.
       * <br>If the natural result is a node set when <code>ANY_TYPE</code> was
       * requested, then <code>UNORDERED_NODE_ITERATOR_TYPE</code> is always
       * the resulting type. Any other representation of a node set must be
       * explicitly requested.
       */
      short ANY_TYPE = 0;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#numbers'>number</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>].
       * Document modification does not invalidate the number, but may mean
       * that reevaluation would not yield the same number.
       */
      short NUMBER_TYPE = 1;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#strings'>string</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>].
       * Document modification does not invalidate the string, but may mean
       * that the string no longer corresponds to the current document.
       */
      short STRING_TYPE = 2;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#booleans'>boolean</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>].
       * Document modification does not invalidate the boolean, but may mean
       * that reevaluation would not yield the same boolean.
       */
      short BOOLEAN_TYPE = 3;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#node-sets'>node set</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>] that
       * will be accessed iteratively, which may not produce nodes in a
       * particular order. Document modification invalidates the iteration.
       * <br>This is the default type returned if the result is a node set and
       * <code>ANY_TYPE</code> is requested.
       */
      short UNORDERED_NODE_ITERATOR_TYPE = 4;
      /**
       * The result is a node set as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>] that
       * will be accessed iteratively, which will produce document-ordered
       * nodes. Document modification invalidates the iteration.
       */
      short ORDERED_NODE_ITERATOR_TYPE = 5;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#node-sets'>node set</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>] that
       * will be accessed as a snapshot list of nodes that may not be in a
       * particular order. Document modification does not invalidate the
       * snapshot but may mean that reevaluation would not yield the same
       * snapshot and nodes in the snapshot may have been altered, moved, or
       * removed from the document.
       */
      short UNORDERED_NODE_SNAPSHOT_TYPE = 6;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#node-sets'>node set</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>] that
       * will be accessed as a snapshot list of nodes that will be in original
       * document order. Document modification does not invalidate the
       * snapshot but may mean that reevaluation would not yield the same
       * snapshot and nodes in the snapshot may have been altered, moved, or
       * removed from the document.
       */
      short ORDERED_NODE_SNAPSHOT_TYPE = 7;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#node-sets'>node set</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>] and
       * will be accessed as a single node, which may be <code>null</code>if
       * the node set is empty. Document modification does not invalidate the
       * node, but may mean that the result node no longer corresponds to the
       * current document. This is a convenience that permits optimization
       * since the implementation can stop once any node in the resulting set
       * has been found.
       * <br>If there is more than one node in the actual result, the single
       * node returned might not be the first in document order.
       */
      short ANY_UNORDERED_NODE_TYPE = 8;
      /**
       * The result is a <a href='http://www.w3.org/TR/1999/REC-xpath-19991116#node-sets'>node set</a> as defined by [<a href='http://www.w3.org/TR/1999/REC-xpath-19991116'>XPath 1.0</a>] and
       * will be accessed as a single node, which may be <code>null</code> if
       * the node set is empty. Document modification does not invalidate the
       * node, but may mean that the result node no longer corresponds to the
       * current document. This is a convenience that permits optimization
       * since the implementation can stop once the first node in document
       * order of the resulting set has been found.
       * <br>If there are more than one node in the actual result, the single
       * node returned will be the first in document order.
       */
      short FIRST_ORDERED_NODE_TYPE = 9;
  
      /**
       * A code representing the type of this result, as defined by the type
       * constants.
       */
      short getResultType();
  
      /**
       * The value of this number result. If the native double type of the DOM
       * binding does not directly support the exact IEEE 754 result of the
       * XPath expression, then it is up to the definition of the binding to
       * specify how the XPath number is converted to the native binding
       * number.
       *
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>NUMBER_TYPE</code>.
       */
      double getNumberValue()
              throws XPathException;
  
      /**
       * The value of this string result.
       *
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>STRING_TYPE</code>.
       */
      String getStringValue()
              throws XPathException;
  
      /**
       * The value of this boolean result.
       *
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>BOOLEAN_TYPE</code>.
       */
      boolean getBooleanValue()
              throws XPathException;
  
      /**
       * The value of this single node result, which may be <code>null</code>.
       *
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>ANY_UNORDERED_NODE_TYPE</code> or
       *                        <code>FIRST_ORDERED_NODE_TYPE</code>.
       */
      Node getSingleNodeValue()
              throws XPathException;
  
      /**
       * Signifies that the iterator has become invalid. True if
       * <code>resultType</code> is <code>UNORDERED_NODE_ITERATOR_TYPE</code>
       * or <code>ORDERED_NODE_ITERATOR_TYPE</code> and the document has been
       * modified since this result was returned.
       */
      boolean getInvalidIteratorState();
  
      /**
       * The number of nodes in the result snapshot. Valid values for
       * snapshotItem indices are <code>0</code> to
       * <code>snapshotLength-1</code> inclusive.
       *
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>UNORDERED_NODE_SNAPSHOT_TYPE</code> or
       *                        <code>ORDERED_NODE_SNAPSHOT_TYPE</code>.
       */
      int getSnapshotLength()
              throws XPathException;
  
      /**
       * Iterates and returns the next node from the node set or
       * <code>null</code>if there are no more nodes.
       *
       * @return Returns the next node.
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>UNORDERED_NODE_ITERATOR_TYPE</code> or
       *                        <code>ORDERED_NODE_ITERATOR_TYPE</code>.
       * @throws DOMException   INVALID_STATE_ERR: The document has been mutated since the result was
       *                        returned.
       */
      Node iterateNext()
              throws XPathException, DOMException;
  
      /**
       * Returns the <code>index</code>th item in the snapshot collection. If
       * <code>index</code> is greater than or equal to the number of nodes in
       * the list, this method returns <code>null</code>. Unlike the iterator
       * result, the snapshot does not become invalid, but may not correspond
       * to the current document if it is mutated.
       *
       * @param index Index into the snapshot collection.
       * @return The node at the <code>index</code>th position in the
       * <code>NodeList</code>, or <code>null</code> if that is not a valid
       * index.
       * @throws XPathException TYPE_ERR: raised if <code>resultType</code> is not
       *                        <code>UNORDERED_NODE_SNAPSHOT_TYPE</code> or
       *                        <code>ORDERED_NODE_SNAPSHOT_TYPE</code>.
       */
      Node snapshotItem(int index)
              throws XPathException;
  
  }
  