/* * 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; import mf.org.w3c.dom.xpath.XPathException; /** * 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; }