/* * Copyright (c) 1997, 2001, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */package javax.swing.text; /** * Interface to describe a structural piece of a document.  It * is intended to capture the spirit of an SGML element. * * @author  Timothy Prinzing */public interface Element {     /**     * Fetches the document associated with this element.     *     * @return the document     */    public Document getDocument();     /**     * Fetches the parent element.  If the element is a root level     * element returns <code>null</code>.     *     * @return the parent element     */    public Element getParentElement();     /**     * Fetches the name of the element.  If the element is used to     * represent some type of structure, this would be the type     * name.     *     * @return the element name     */    public String getName();     /**     * Fetches the collection of attributes this element contains.     *     * @return the attributes for the element     */    public AttributeSet getAttributes();     /**     * Fetches the offset from the beginning of the document     * that this element begins at.  If this element has     * children, this will be the offset of the first child.     * As a document position, there is an implied forward bias.     *     * @return the starting offset >= 0 and < getEndOffset();     * @see Document     * @see AbstractDocument     */    public int getStartOffset();     /**     * Fetches the offset from the beginning of the document     * that this element ends at.  If this element has     * children, this will be the end offset of the last child.     * As a document position, there is an implied backward bias.     * <p>     * All the default <code>Document</code> implementations     * descend from <code>AbstractDocument</code>.     * <code>AbstractDocument</code> models an implied break at the end of     * the document. As a result of this, it is possible for this to     * return a value greater than the length of the document.     *     * @return the ending offset > getStartOffset() and     *     <= getDocument().getLength() + 1     * @see Document     * @see AbstractDocument     */    public int getEndOffset();     /**     * Gets the child element index closest to the given offset.     * The offset is specified relative to the beginning of the     * document.  Returns <code>-1</code> if the     * <code>Element</code> is a leaf, otherwise returns     * the index of the <code>Element</code> that best represents     * the given location.  Returns <code>0</code> if the location     * is less than the start offset. Returns     * <code>getElementCount() - 1</code> if the location is     * greater than or equal to the end offset.     *     * @param offset the specified offset >= 0     * @return the element index >= 0     */    public int getElementIndex(int offset);     /**     * Gets the number of child elements contained by this element.     * If this element is a leaf, a count of zero is returned.     *     * @return the number of child elements >= 0     */    public int getElementCount();     /**     * Fetches the child element at the given index.     *     * @param index the specified index >= 0     * @return the child element     */    public Element getElement(int index);     /**     * Is this element a leaf element? An element that     * <i>may</i> have children, even if it currently     * has no children, would return <code>false</code>.     *     * @return true if a leaf element else false     */    public boolean isLeaf();  }