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/*
* 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 org.w3c.dom.xpath;
import org.w3c.dom.Node;
import org.w3c.dom.DOMException;
/**
* 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final 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.
*/
public static final short FIRST_ORDERED_NODE_TYPE = 9;
/**
* A code representing the type of this result, as defined by the type
* constants.
*/
public 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.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>NUMBER_TYPE</code>.
*/
public double getNumberValue()
throws XPathException;
/**
* The value of this string result.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>STRING_TYPE</code>.
*/
public String getStringValue()
throws XPathException;
/**
* The value of this boolean result.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>BOOLEAN_TYPE</code>.
*/
public boolean getBooleanValue()
throws XPathException;
/**
* The value of this single node result, which may be <code>null</code>.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>ANY_UNORDERED_NODE_TYPE</code> or
* <code>FIRST_ORDERED_NODE_TYPE</code>.
*/
public 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.
*/
public 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.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>UNORDERED_NODE_SNAPSHOT_TYPE</code> or
* <code>ORDERED_NODE_SNAPSHOT_TYPE</code>.
*/
public 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.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>UNORDERED_NODE_ITERATOR_TYPE</code> or
* <code>ORDERED_NODE_ITERATOR_TYPE</code>.
* @exception DOMException
* INVALID_STATE_ERR: The document has been mutated since the result was
* returned.
*/
public 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.
* @exception XPathException
* TYPE_ERR: raised if <code>resultType</code> is not
* <code>UNORDERED_NODE_SNAPSHOT_TYPE</code> or
* <code>ORDERED_NODE_SNAPSHOT_TYPE</code>.
*/
public Node snapshotItem(int index)
throws XPathException;
}