org.w3c.dom.xpath.XPathResult Maven / Gradle / Ivy
/*
* Copyright (c) 2002 World Wide Web Consortium,
* (Massachusetts Institute of Technology, Institut National de
* Recherche en Informatique et en Automatique, Keio University). All
* Rights Reserved. This program is distributed under the W3C's Software
* Intellectual Property License. This program is distributed 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.
* See W3C License http://www.w3.org/Consortium/Legal/ for more details.
*/
package org.w3c.dom.xpath;
import org.w3c.dom.Node;
import org.w3c.dom.DOMException;
/**
*
* DOM Level 3 WD Experimental:
* The DOM Level 3 specification is at the stage
* of Working Draft, which represents work in
* progress and thus may be updated, replaced,
* or obsoleted by other documents at any time.
* The XPathResult interface represents the result of the
* evaluation of an XPath 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.Should there be a flag on the result to
* say whether an iteration has become invalid?Yes.Added the boolean
* attribute invalidIteratorStateShould there be a reset method
* on the result in case someone wants to iterate the result multiple times?
* It may be more trouble than it is worth, because the user can request a
* new query. See if there are use cases.It might be better to consolidate
* the interfaces and just move the snapshot and iterator functions to the
* result object.Yes.The result of the consolidation looks good and unless
* there are great objections, this is how it will be.There is concern that
* the result cannot represent multiple strings, which is a possible result
* of XPath 2.0. on them?No change.This is not part of the XPath 1.0 data
* model. We cannot plan well for the XPath 2.0 data model at this point.
* Most likely a new API will be required for XPath 2.0
*
See also the Document Object Model (DOM) Level 3 XPath Specification.
*/
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.
*
If the natural result is a node set when ANY_TYPE was
* requested, then UNORDERED_NODE_ITERATOR_TYPE 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 number as defined by . 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 string as defined by . 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 boolean as defined by . 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 node set as defined by that will be accessed
* iteratively, which may not produce nodes in a particular order.
* Document modification invalidates the iteration.
*
This is the default type returned if the result is a node set and
* ANY_TYPE is requested.
*/
public static final short UNORDERED_NODE_ITERATOR_TYPE = 4;
/**
* The result is a node set as defined by 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 node set as defined by 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 node set as defined by 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 node set as defined by and will be accessed as a
* single node, which may be nullif 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 in the resulting set has been found.
*
If there are more than one node in the actual result, the single
* node returned may not be the first in document order.
*/
public static final short ANY_UNORDERED_NODE_TYPE = 8;
/**
* The result is a node set as defined by and will be accessed as a
* single node, which may be null 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.
*
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.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* NUMBER_TYPE.
*/
public double getNumberValue()
throws XPathException;
/**
* The value of this string result.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* STRING_TYPE.
*/
public String getStringValue()
throws XPathException;
/**
* The value of this boolean result.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* BOOLEAN_TYPE.
*/
public boolean getBooleanValue()
throws XPathException;
/**
* The value of this single node result, which may be null.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* ANY_UNORDERED_NODE_TYPE or
* FIRST_ORDERED_NODE_TYPE.
*/
public Node getSingleNodeValue()
throws XPathException;
/**
* Signifies that the iterator has become invalid. True if
* resultType is UNORDERED_NODE_ITERATOR_TYPE
* or ORDERED_NODE_ITERATOR_TYPE 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 0 to
* snapshotLength-1 inclusive.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* UNORDERED_NODE_SNAPSHOT_TYPE or
* ORDERED_NODE_SNAPSHOT_TYPE.
*/
public int getSnapshotLength()
throws XPathException;
/**
* Iterates and returns the next node from the node set or
* nullif there are no more nodes.
* @return Returns the next node.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* UNORDERED_NODE_ITERATOR_TYPE or
* ORDERED_NODE_ITERATOR_TYPE.
* @exception DOMException
* INVALID_STATE_ERR: The document has been mutated since the result was
* returned.
*/
public Node iterateNext()
throws XPathException, DOMException;
/**
* Returns the indexth item in the snapshot collection. If
* index is greater than or equal to the number of nodes in
* the list, this method returns null. 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 indexth position in the
* NodeList, or null if that is not a valid
* index.
* @exception XPathException
* TYPE_ERR: raised if resultType is not
* UNORDERED_NODE_SNAPSHOT_TYPE or
* ORDERED_NODE_SNAPSHOT_TYPE.
*/
public Node snapshotItem(int index)
throws XPathException;
}