| /* |
| * Copyright (c) 2009 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; |
| |
| /** |
| * The <code>ElementTraversal</code> interface is a set of read-only attributes |
| * which allow an author to easily navigate between elements in a document. |
| * <p>In conforming implementations of Element Traversal, all objects that |
| * implement {@link Element} must also implement the |
| * <code>ElementTraversal</code> interface. Four of the methods, |
| * {@link #getFirstElementChild}, {@link #getLastElementChild}, |
| * {@link #getPreviousElementSibling}, and {@link #getNextElementSibling}, |
| * each return a live reference to another element with the defined |
| * relationship to the current element, if the related element exists. The |
| * fifth method, {@link #getChildElementCount}, exposes the number of child |
| * elements of an element, for preprocessing before navigation. |
| * <p>See also the |
| * <a href='http://www.w3.org/TR/ElementTraversal/'><cite>Element Traversal Specification</cite></a>. |
| */ |
| public interface ElementTraversal { |
| |
| /** |
| * Returns the first child element node of this element. <code>null</code> |
| * if this element has no child elements. |
| */ |
| Element getFirstElementChild(); |
| |
| /** |
| * Returns the last child element node of this element. <code>null</code> |
| * if this element has no child elements. |
| */ |
| Element getLastElementChild(); |
| |
| /** |
| * Returns the previous sibling element node of this element. |
| * <code>null</code> if this element has no element sibling nodes that |
| * come before this one in the document tree. |
| */ |
| Element getPreviousElementSibling(); |
| |
| /** |
| * Returns the next sibling element node of this element. |
| * <code>null</code> if this element has no element sibling nodes that |
| * come after this one in the document tree. |
| */ |
| Element getNextElementSibling(); |
| |
| /** |
| * Returns the current number of element nodes that are children of this |
| * element. <code>0</code> if this element has no child nodes that are of |
| * <code>nodeType</code> <code>1</code>. |
| */ |
| int getChildElementCount(); |
| } |