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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * 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.

 *

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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();

}