/*

  * 

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

  * 

  * Copyright 2007-2008 Sun Microsystems, Inc. All rights reserved.

  * 

  * The contents of this file are subject to the terms of either the GNU

  * General Public License Version 2 only ("GPL") or the Common Development

  * and Distribution License("CDDL") (collectively, the "License").  You

  * may not use this file except in compliance with the License. You can obtain

  * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html

  * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific

  * language governing permissions and limitations under the License.

  * 

  * When distributing the software, include this License Header Notice in each

  * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.

  * Sun designates this particular file as subject to the "Classpath" exception

  * as provided by Sun in the GPL Version 2 section of the License file that

  * accompanied this code.  If applicable, add the following below the License

  * Header, with the fields enclosed by brackets [] replaced by your own

  * identifying information: "Portions Copyrighted [year]

  * [name of copyright owner]"

  * 

  * Contributor(s):

  * 

  * If you wish your version of this file to be governed by only the CDDL or

  * only the GPL Version 2, indicate your decision by adding "[Contributor]

  * elects to include this software in this distribution under the [CDDL or GPL

  * Version 2] license."  If you don't indicate a single choice of license, a

  * recipient has the option to distribute your version of this file under

  * either the CDDL, the GPL Version 2 or to extend the choice of license to

  * its licensees as provided above.  However, if you add GPL Version 2 code

  * and therefore, elected the GPL Version 2 license, then the option applies

  * only if the new code is made subject to such option by the copyright

  * holder.

  *

  */

 package com.sun.grizzly;

 import com.sun.grizzly.util.Copyable;

 import com.sun.grizzly.util.SelectionKeyActionAttachment;

 import com.sun.grizzly.util.SelectionKeyAttachment;

 import java.io.IOException;

 import java.net.Socket;

 import java.nio.channels.ClosedChannelException;

 import java.nio.channels.SelectableChannel;

 import java.nio.channels.SelectionKey;

 import java.nio.channels.Selector;

 import java.nio.channels.SocketChannel;

 import java.util.Iterator;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 /**

  * This class is an implementation of a SelectionKeyHandler which does 

  * not use the SelectionKey attachment, does not expire keys or utilize 

  * a keep-alive mechanism. However, this is currently not the 

  * SelectionKeyHandler provisioned by default with Grizzly's Controller. 

  * Hence for an application to use this SelectionKeyHandler, Grizzly's

  * Controller must be explicitly configured to use this SelectionKeyHandler

  * implementation.

  * 

  * @author Charlie Hunt

  */

 public class BaseSelectionKeyHandler implements SelectionKeyHandler {

     protected Logger logger = Controller.logger();

     /**

      * Associated {@link SelectorHandler}

      */

     protected SelectorHandler selectorHandler;

     public BaseSelectionKeyHandler() {

     }

     public BaseSelectionKeyHandler(SelectorHandler selectorHandler) {

         this.selectorHandler = selectorHandler;

     }

     /**

      * {@inheritDoc}

      */

     public SelectorHandler getSelectorHandler() {

         return selectorHandler;

     } 

     /**

      * {@inheritDoc}

      */

     public void setSelectorHandler(SelectorHandler selectorHandler) {

         this.selectorHandler = selectorHandler;

     }

     /**

      * {@inheritDoc}

      */

     public void process(SelectionKey key) {

         Object attachment = key.attachment();

         // NOTE: If attachment == null, instanceof will evaluate to false.

         //       If attachment == null does not generate NullPointerException

         if (attachment instanceof SelectionKeyActionAttachment) {

             ((SelectionKeyActionAttachment) attachment).process(key);

         }

     }

     /**

      * {@inheritDoc}

      */

     public void postProcess(SelectionKey key) {

         Object attachment = key.attachment();

         // NOTE: If attachment == null, instanceof will evaluate to false.

         //       If attachment == null does not generate NullPointerException

         if (attachment instanceof SelectionKeyActionAttachment) {

             ((SelectionKeyActionAttachment) attachment).postProcess(key);

         }

     }

     /**

      * @deprecated

      */

     public void register(SelectionKey key, long currentTime) {

         throw new UnsupportedOperationException(getClass().getName() + 

                         " use of this API not allowed.");

     }

     /**

      * {@inheritDoc}

      */

     public void register(SelectionKey key, int selectionKeyOps) {

         doRegisterKey(key, selectionKeyOps);

     }

     /**

      * Registers {@link SelectionKey} to handle certain operations

      */

     protected void doRegisterKey(SelectionKey key, int selectionKeyOps) {

         if (!key.isValid()) {

             return;

         }

         key.interestOps(key.interestOps() | selectionKeyOps);

     }

     /**

      * {@inheritDoc}

      */

     public void register(SelectableChannel channel, int selectionKeyOps) throws ClosedChannelException {

         if (!channel.isOpen()) {

             return;

         }

         Selector selector = selectorHandler.getSelector();

         SelectionKey key = channel.keyFor(selector);

         if (key == null) {

             channel.register(selector, selectionKeyOps);

         } else {

             doRegisterKey(key, selectionKeyOps);

         }

     }

     /**

      * {@inheritDoc}

      */

     public void register(Iterator<SelectionKey> keyIterator, int selectionKeyOps) {

         SelectionKey key;

         while (keyIterator.hasNext()) {

             key = keyIterator.next();

             keyIterator.remove();

             doRegisterKey(key, selectionKeyOps);

         }

     }

     /**

      * @deprecated

      */

     public void expire(SelectionKey key, long currentTime) {

         // Do nothing.

     }

     /**

      * {@inheritDoc}

      */

     public void expire(Iterator<SelectionKey> keyIterator) {

         // Do nothing.

     }

     /**

      * Cancel a SelectionKey and close its associated Channel.

      * @param key {@link SelectionKey} to cancel

      */

     public void cancel(SelectionKey key) {

         if (!keyIsValid(key)) {

             return;

         }

         closeChannel(key);

         clearKeyAttachment(key);

         cancelKey(key);

     }

     /**

      * {@inheritDoc}

      */

     public void close(SelectionKey key) {

         cancel(key);

     }

     /**

      * {@inheritDoc}

      */

     public void copyTo(Copyable copy) {

         BaseSelectionKeyHandler copyHandler = (BaseSelectionKeyHandler) copy;

         copyHandler.selectorHandler = selectorHandler;

     }

     public Logger getLogger() {

         return logger;

     }

     public void setLogger(Logger logger) {

         this.logger = logger;

     }

     protected void cancelKey(SelectionKey key) {

         key.cancel();

         key = null;

     }

     protected boolean keyIsValid(SelectionKey key) {

         if (key != null && key.isValid()) {

             return true;

         } else {

             return false;

         }

     }

     protected void closeChannel(SelectionKey key) {

         if (selectorHandler != null) {

             selectorHandler.closeChannel(key.channel());

         } else {

             closeChannel(key.channel());

         }

     }

     protected Object clearKeyAttachment(SelectionKey key) {

         Object attachment = key.attach(null);

         if (attachment instanceof SelectionKeyAttachment) {

             ((SelectionKeyAttachment) attachment).release(key);

         }

         return attachment;

     }

     protected void closeChannel(SelectableChannel channel) {

         try {

             if (channel instanceof SocketChannel) {

                 Socket socket = ((SocketChannel) channel).socket();

                 try {

                     if (!socket.isInputShutdown()) {

                         socket.shutdownInput();

                     }

                 } catch (IOException ex) {

                     Logger.getLogger(BaseSelectionKeyHandler.class.getName()).

                                log(Level.FINE, null, ex);

                 }

                 try {

                     if (!socket.isOutputShutdown()) {

                         socket.shutdownOutput();

                     }

                 } catch (IOException ex) {

                     Logger.getLogger(BaseSelectionKeyHandler.class.getName()).

                                log(Level.FINE, null, ex);

                 }

                 try {

                     socket.close();

                 } catch (IOException ex) {

                     Logger.getLogger(BaseSelectionKeyHandler.class.getName()).

                                log(Level.FINE, null, ex);

                 }

             }

             channel.close();

         } catch (IOException ex) {

             Logger.getLogger(BaseSelectionKeyHandler.class.getName()).

                        log(Level.FINE, null, ex);

         }

     }

 }