/* * Copyright (c) 1998, 2000, 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.accessibility;  import java.util.*;import java.awt.*;import javax.swing.text.*;  /** * Encapsulation of a link, or set of links (e.g. client side imagemap) * in a Hypertext document * * @see Accessible * @see Accessible#getAccessibleContext * @see AccessibleContext * @see AccessibleText * @see AccessibleContext#getAccessibleText * * @author      Peter Korn */public abstract class AccessibleHyperlink implements AccessibleAction {         /**         * Since the document a link is associated with may have         * changed, this method returns whether or not this Link is still valid         * (with respect to the document it references).         *         * @return a flag indicating whether this link is still valid with         *         respect to the AccessibleHypertext it belongs to         */        public abstract boolean isValid();         /**         * Returns the number of accessible actions available in this Link         * If there are more than one, the first one is NOT considered the         * "default" action of this LINK object (e.g. in an HTML imagemap).         * In general, links will have only one AccessibleAction in them.         *         * @return the zero-based number of Actions in this object         */        public abstract int getAccessibleActionCount();         /**         * Performs the specified Action on the object         *         * @param i zero-based index of actions         * @return true if the action was performed; otherwise false.         * @see #getAccessibleActionCount         */        public abstract boolean doAccessibleAction(int i);         /**         * Returns a String description of this particular         * link action.  This should be a text string         * associated with anchoring text, this should be the         * anchor text.  E.g. from HTML:         *   <a HREF="http://www.sun.com/access">Accessibility</a>         * this method would return "Accessibility".         *         * Similarly, from this HTML:         *   <a HREF="#top"><img src="top-hat.gif" alt="top hat"></a>         * this method would return "top hat"         *         * @param i zero-based index of the actions         * @return a String description of the action         * @see #getAccessibleActionCount         */        public abstract String getAccessibleActionDescription(int i);         /**         * Returns an object that represents the link action,         * as appropriate for that link.  E.g. from HTML:         *   <a HREF="http://www.sun.com/access">Accessibility</a>         * this method would return a         * java.net.URL("http://www.sun.com/access.html");         *         * @param i zero-based index of the actions         * @return an Object representing the hypertext link itself         * @see #getAccessibleActionCount         */        public abstract Object getAccessibleActionObject(int i);         /**         * Returns an object that represents the link anchor,         * as appropriate for that link.  E.g. from HTML:         *   <a href="http://www.sun.com/access">Accessibility</a>         * this method would return a String containing the text:         * "Accessibility".         *         * Similarly, from this HTML:         *   <a HREF="#top"><img src="top-hat.gif" alt="top hat"></a>         * this might return the object ImageIcon("top-hat.gif", "top hat");         *         * @param i zero-based index of the actions         * @return an Object representing the hypertext anchor         * @see #getAccessibleActionCount         */        public abstract Object getAccessibleActionAnchor(int i);         /**         * Gets the index with the hypertext document at which this         * link begins         *         * @return index of start of link         */        public abstract int getStartIndex();         /**         * Gets the index with the hypertext document at which this         * link ends         *         * @return index of end of link         */        public abstract int getEndIndex();}