001/*
002 * Copyright (c) 2000 World Wide Web Consortium,
003 * (Massachusetts Institute of Technology, Institut National de
004 * Recherche en Informatique et en Automatique, Keio University). All
005 * Rights Reserved. This program is distributed under the W3C's Software
006 * Intellectual Property License. This program is distributed in the
007 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
008 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
009 * PURPOSE.
010 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
011 */
012
013package org.w3c.dom.traversal;
014
015import org.w3c.dom.Node;
016import org.w3c.dom.DOMException;
017
018/**
019 * <code>DocumentTraversal</code> contains methods that create
020 * <code>NodeIterators</code> and <code>TreeWalkers</code> to traverse a
021 * node and its children in document order (depth first, pre-order
022 * traversal, which is equivalent to the order in which the start tags occur
023 * in the text representation of the document). In DOMs which support the
024 * Traversal feature, <code>DocumentTraversal</code> will be implemented by
025 * the same objects that implement the Document interface.
026 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Traversal-Range-20001113'>Document Object Model (DOM) Level 2 Traversal and Range Specification</a>.
027 * @since DOM Level 2
028 */
029public interface DocumentTraversal {
030    /**
031     * Create a new <code>NodeIterator</code> over the subtree rooted at the
032     * specified node.
033     * @param root The node which will be iterated together with its
034     *   children. The <code>NodeIterator</code> is initially positioned
035     *   just before this node. The <code>whatToShow</code> flags and the
036     *   filter, if any, are not considered when setting this position. The
037     *   root must not be <code>null</code>.
038     * @param whatToShow This flag specifies which node types may appear in
039     *   the logical view of the tree presented by the
040     *   <code>NodeIterator</code>. See the description of
041     *   <code>NodeFilter</code> for the set of possible <code>SHOW_</code>
042     *   values.These flags can be combined using <code>OR</code>.
043     * @param filter The <code>NodeFilter</code> to be used with this
044     *   <code>NodeIterator</code>, or <code>null</code> to indicate no
045     *   filter.
046     * @param entityReferenceExpansion The value of this flag determines
047     *   whether entity reference nodes are expanded.
048     * @return The newly created <code>NodeIterator</code>.
049     * @exception DOMException
050     *   NOT_SUPPORTED_ERR: Raised if the specified <code>root</code> is
051     *   <code>null</code>.
052     */
053    public NodeIterator createNodeIterator(Node root,
054                                           int whatToShow,
055                                           NodeFilter filter,
056                                           boolean entityReferenceExpansion)
057                                           throws DOMException;
058
059    /**
060     * Create a new <code>TreeWalker</code> over the subtree rooted at the
061     * specified node.
062     * @param root The node which will serve as the <code>root</code> for the
063     *   <code>TreeWalker</code>. The <code>whatToShow</code> flags and the
064     *   <code>NodeFilter</code> are not considered when setting this value;
065     *   any node type will be accepted as the <code>root</code>. The
066     *   <code>currentNode</code> of the <code>TreeWalker</code> is
067     *   initialized to this node, whether or not it is visible. The
068     *   <code>root</code> functions as a stopping point for traversal
069     *   methods that look upward in the document structure, such as
070     *   <code>parentNode</code> and nextNode. The <code>root</code> must
071     *   not be <code>null</code>.
072     * @param whatToShow This flag specifies which node types may appear in
073     *   the logical view of the tree presented by the
074     *   <code>TreeWalker</code>. See the description of
075     *   <code>NodeFilter</code> for the set of possible <code>SHOW_</code>
076     *   values.These flags can be combined using <code>OR</code>.
077     * @param filter The <code>NodeFilter</code> to be used with this
078     *   <code>TreeWalker</code>, or <code>null</code> to indicate no filter.
079     * @param entityReferenceExpansion If this flag is false, the contents of
080     *   <code>EntityReference</code> nodes are not presented in the logical
081     *   view.
082     * @return The newly created <code>TreeWalker</code>.
083     * @exception DOMException
084     *    NOT_SUPPORTED_ERR: Raised if the specified <code>root</code> is
085     *   <code>null</code>.
086     */
087    public TreeWalker createTreeWalker(Node root,
088                                       int whatToShow,
089                                       NodeFilter filter,
090                                       boolean entityReferenceExpansion)
091                                       throws DOMException;
092
093}