- /*
- * Copyright (c) 2000 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.traversal;
-
- import org.w3c.dom.Node;
- import org.w3c.dom.DOMException;
-
- /**
- * <code>TreeWalker</code> objects are used to navigate a document tree or
- * subtree using the view of the document defined by their
- * <code>whatToShow</code> flags and filter (if any). Any function which
- * performs navigation using a <code>TreeWalker</code> will automatically
- * support any view defined by a <code>TreeWalker</code>.
- * <p>Omitting nodes from the logical view of a subtree can result in a
- * structure that is substantially different from the same subtree in the
- * complete, unfiltered document. Nodes that are siblings in the
- * <code>TreeWalker</code> view may be children of different, widely
- * separated nodes in the original view. For instance, consider a
- * <code>NodeFilter</code> that skips all nodes except for Text nodes and
- * the root node of a document. In the logical view that results, all text
- * nodes will be siblings and appear as direct children of the root node, no
- * matter how deeply nested the structure of the original document.
- * <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>.
- * @since DOM Level 2
- */
- public interface TreeWalker {
- /**
- * The <code>root</code> node of the <code>TreeWalker</code>, as specified
- * when it was created.
- */
- public Node getRoot();
-
- /**
- * This attribute determines which node types are presented via the
- * <code>TreeWalker</code>. The available set of constants is defined in
- * the <code>NodeFilter</code> interface. Nodes not accepted by
- * <code>whatToShow</code> will be skipped, but their children may still
- * be considered. Note that this skip takes precedence over the filter,
- * if any.
- */
- public int getWhatToShow();
-
- /**
- * The filter used to screen nodes.
- */
- public NodeFilter getFilter();
-
- /**
- * The value of this flag determines whether the children of entity
- * reference nodes are visible to the <code>TreeWalker</code>. If false,
- * these children and their descendants will be rejected. Note that
- * this rejection takes precedence over <code>whatToShow</code> and the
- * filter, if any.
- * <br> To produce a view of the document that has entity references
- * expanded and does not expose the entity reference node itself, use
- * the <code>whatToShow</code> flags to hide the entity reference node
- * and set <code>expandEntityReferences</code> to true when creating the
- * <code>TreeWalker</code>. To produce a view of the document that has
- * entity reference nodes but no entity expansion, use the
- * <code>whatToShow</code> flags to show the entity reference node and
- * set <code>expandEntityReferences</code> to false.
- */
- public boolean getExpandEntityReferences();
-
- /**
- * The node at which the <code>TreeWalker</code> is currently positioned.
- * <br>Alterations to the DOM tree may cause the current node to no longer
- * be accepted by the <code>TreeWalker</code>'s associated filter.
- * <code>currentNode</code> may also be explicitly set to any node,
- * whether or not it is within the subtree specified by the
- * <code>root</code> node or would be accepted by the filter and
- * <code>whatToShow</code> flags. Further traversal occurs relative to
- * <code>currentNode</code> even if it is not part of the current view,
- * by applying the filters in the requested direction; if no traversal
- * is possible, <code>currentNode</code> is not changed.
- * @exception DOMException
- * NOT_SUPPORTED_ERR: Raised if an attempt is made to set
- * <code>currentNode</code> to <code>null</code>.
- */
- public Node getCurrentNode();
- /**
- * The node at which the <code>TreeWalker</code> is currently positioned.
- * <br>Alterations to the DOM tree may cause the current node to no longer
- * be accepted by the <code>TreeWalker</code>'s associated filter.
- * <code>currentNode</code> may also be explicitly set to any node,
- * whether or not it is within the subtree specified by the
- * <code>root</code> node or would be accepted by the filter and
- * <code>whatToShow</code> flags. Further traversal occurs relative to
- * <code>currentNode</code> even if it is not part of the current view,
- * by applying the filters in the requested direction; if no traversal
- * is possible, <code>currentNode</code> is not changed.
- * @exception DOMException
- * NOT_SUPPORTED_ERR: Raised if an attempt is made to set
- * <code>currentNode</code> to <code>null</code>.
- */
- public void setCurrentNode(Node currentNode)
- throws DOMException;
-
- /**
- * Moves to and returns the closest visible ancestor node of the current
- * node. If the search for <code>parentNode</code> attempts to step
- * upward from the <code>TreeWalker</code>'s <code>root</code> node, or
- * if it fails to find a visible ancestor node, this method retains the
- * current position and returns <code>null</code>.
- * @return The new parent node, or <code>null</code> if the current node
- * has no parent in the <code>TreeWalker</code>'s logical view.
- */
- public Node parentNode();
-
- /**
- * Moves the <code>TreeWalker</code> to the first visible child of the
- * current node, and returns the new node. If the current node has no
- * visible children, returns <code>null</code>, and retains the current
- * node.
- * @return The new node, or <code>null</code> if the current node has no
- * visible children in the <code>TreeWalker</code>'s logical view.
- */
- public Node firstChild();
-
- /**
- * Moves the <code>TreeWalker</code> to the last visible child of the
- * current node, and returns the new node. If the current node has no
- * visible children, returns <code>null</code>, and retains the current
- * node.
- * @return The new node, or <code>null</code> if the current node has no
- * children in the <code>TreeWalker</code>'s logical view.
- */
- public Node lastChild();
-
- /**
- * Moves the <code>TreeWalker</code> to the previous sibling of the
- * current node, and returns the new node. If the current node has no
- * visible previous sibling, returns <code>null</code>, and retains the
- * current node.
- * @return The new node, or <code>null</code> if the current node has no
- * previous sibling. in the <code>TreeWalker</code>'s logical view.
- */
- public Node previousSibling();
-
- /**
- * Moves the <code>TreeWalker</code> to the next sibling of the current
- * node, and returns the new node. If the current node has no visible
- * next sibling, returns <code>null</code>, and retains the current node.
- * @return The new node, or <code>null</code> if the current node has no
- * next sibling. in the <code>TreeWalker</code>'s logical view.
- */
- public Node nextSibling();
-
- /**
- * Moves the <code>TreeWalker</code> to the previous visible node in
- * document order relative to the current node, and returns the new
- * node. If the current node has no previous node, or if the search for
- * <code>previousNode</code> attempts to step upward from the
- * <code>TreeWalker</code>'s <code>root</code> node, returns
- * <code>null</code>, and retains the current node.
- * @return The new node, or <code>null</code> if the current node has no
- * previous node in the <code>TreeWalker</code>'s logical view.
- */
- public Node previousNode();
-
- /**
- * Moves the <code>TreeWalker</code> to the next visible node in document
- * order relative to the current node, and returns the new node. If the
- * current node has no next node, or if the search for nextNode attempts
- * to step upward from the <code>TreeWalker</code>'s <code>root</code>
- * node, returns <code>null</code>, and retains the current node.
- * @return The new node, or <code>null</code> if the current node has no
- * next node in the <code>TreeWalker</code>'s logical view.
- */
- public Node nextNode();
-
- }