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  * 

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

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

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  * 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

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 package com.sun.grizzly;

 import com.sun.grizzly.async.UDPAsyncQueueReader;

 import com.sun.grizzly.async.UDPAsyncQueueWriter;

 import com.sun.grizzly.util.CallbackHandlerSelectionKeyAttachment;

 import com.sun.grizzly.util.Copyable;

 import com.sun.grizzly.util.SelectionKeyOP;

 import com.sun.grizzly.util.State;

 import java.io.IOException;

 import java.net.BindException;

 import java.net.DatagramSocket;

 import java.net.InetSocketAddress;

 import java.net.SocketAddress;

 import java.net.SocketException;

 import java.nio.channels.DatagramChannel;

 import java.nio.channels.SelectableChannel;

 import java.nio.channels.SelectionKey;

 import java.nio.channels.Selector;

 import java.util.concurrent.Callable;

 import java.util.logging.Level;

 /**

  * A SelectorHandler handles all java.nio.channels.Selector operations. 

  * One or more instance of a Selector are handled by SelectorHandler. 

  * The logic for processing of SelectionKey interest (OP_ACCEPT,OP_READ, etc.)

  * is usually defined using an instance of SelectorHandler.

  *

  * This class represent a UDP implementation of a SelectorHandler. 

  * This class first bind a datagramSocketChannel to a UDP port and then start 

  * waiting for NIO events. 

  *

  * @author Jeanfrancois Arcand

  */

 public class UDPSelectorHandler extends TCPSelectorHandler {

     private final static String NOT_SUPPORTED = 

             "Not supported by this SelectorHandler";

     /**

      * The datagramSocket instance.

      */

     protected DatagramSocket datagramSocket;

     /**

      * The DatagramChannel.

      */

     protected DatagramChannel datagramChannel;    

     public UDPSelectorHandler() {

         this(Role.CLIENT_SERVER);

     }

     public UDPSelectorHandler(boolean isClient) {

         this(boolean2Role(isClient));

     }

     public UDPSelectorHandler(Role role) {

         super(role);

     }

     @Override

     public void copyTo(Copyable copy) {

         super.copyTo(copy);

         UDPSelectorHandler copyHandler = (UDPSelectorHandler) copy;

         copyHandler.datagramSocket = datagramSocket;

         copyHandler.datagramChannel= datagramChannel;

     }

     /**

      * Before invoking Selector.select(), make sure the ServerScoketChannel

      * has been created. If true, then register all SelectionKey to the Selector.

      */

     @Override

     public void preSelect(Context ctx) throws IOException {

         initOpRegistriesIfRequired();

         if (asyncQueueReader == null) {

             asyncQueueReader = new UDPAsyncQueueReader(this);

         }

         if (asyncQueueWriter == null) {

             asyncQueueWriter = new UDPAsyncQueueWriter(this);

         }

         if (selector == null){

             try{

                 isShutDown.set(false);

                 connectorInstanceHandler = new ConnectorInstanceHandler.

                         ConcurrentQueueDelegateCIH(

                         getConnectorInstanceHandlerDelegate());

                 datagramChannel = DatagramChannel.open();

                 selector = Selector.open();

                 if (role != Role.CLIENT){

                     datagramSocket = datagramChannel.socket();

                     datagramSocket.setReuseAddress(reuseAddress);

                     if (inet == null)

                         datagramSocket.bind(new InetSocketAddress(port));

                     else

                         datagramSocket.bind(new InetSocketAddress(inet,port));

                     datagramChannel.configureBlocking(false);

                     datagramChannel.register( selector, SelectionKey.OP_READ );

                     datagramSocket.setSoTimeout(serverTimeout); 

                 } 

                 ctx.getController().notifyReady();

             } catch (SocketException ex){

                 throw new BindException(ex.getMessage() + ": " + port);

             }

         } else {

             processPendingOperations(ctx);

         }

     }

     /**

      * Handle new OP_CONNECT ops.

      */

     @Override

     protected void onConnectOp(Context ctx, 

             SelectionKeyOP.ConnectSelectionKeyOP selectionKeyOp) throws IOException {

         SocketAddress remoteAddress = selectionKeyOp.getRemoteAddress();

         SocketAddress localAddress = selectionKeyOp.getLocalAddress();

         CallbackHandler callbackHandler = selectionKeyOp.getCallbackHandler();

         final DatagramChannel datagramChannel = DatagramChannel.open();

         datagramChannel.socket().setReuseAddress(reuseAddress);

         if (localAddress != null) {

             datagramChannel.socket().bind(localAddress);

         }

         datagramChannel.configureBlocking(false);

         datagramChannel.connect(remoteAddress);

         SelectionKey key = datagramChannel.register(selector, 

                 SelectionKey.OP_READ | SelectionKey.OP_WRITE);

         key.attach(CallbackHandlerSelectionKeyAttachment.create(key, callbackHandler));

         onConnectInterest(key, ctx);

     }

     /**

      * Shuntdown this instance by closing its Selector and associated channels.

      */

     @Override

     public void shutdown(){

         // If shutdown was called for this SelectorHandler

         if (isShutDown.getAndSet(true)) return;

         stateHolder.setState(State.STOPPED);

         try {

             if ( datagramSocket != null )

                 datagramSocket.close();

         } catch (Throwable ex){

             Controller.logger().log(Level.SEVERE,

                     "closeSocketException",ex);

         }

         try{

             if ( datagramChannel != null)

                 datagramChannel.close();

         } catch (Throwable ex){

             Controller.logger().log(Level.SEVERE,

                     "closeSocketException",ex);

         }

         try{

             if ( selector != null)

                 selector.close();

         } catch (Throwable ex){

             Controller.logger().log(Level.SEVERE,

                     "closeSocketException",ex);

         }

         if (asyncQueueReader != null) {

             asyncQueueReader.close();

             asyncQueueReader = null;

         }

         if (asyncQueueWriter != null) {

             asyncQueueWriter.close();

             asyncQueueWriter = null;

         }

     }

     /**

      * Handle OP_ACCEPT. Not used for UPD.

      */

     @Override

     public boolean onAcceptInterest(SelectionKey key, Context ctx) throws IOException{

         return false;

     }

     /**

      * {@inheritDoc}

      */

     @Override

     public Class<? extends SelectionKeyHandler> getPreferredSelectionKeyHandler() {

         return BaseSelectionKeyHandler.class;

     }

     /**

      * A token describing the protocol supported by an implementation of this

      * interface

      */

     @Override

     public Controller.Protocol protocol(){

         return Controller.Protocol.UDP;

     }   

     @Override

     public int getPortLowLevel() {

         if (datagramSocket != null) {

             return datagramSocket.getLocalPort();

         }

         return -1;

     }

     @Override

     public int getSsBackLog() {

         throw new IllegalStateException(NOT_SUPPORTED);

     }

     @Override

     public void setSsBackLog(int ssBackLog) {

         throw new IllegalStateException(NOT_SUPPORTED);

     }

     @Override

     public boolean isTcpNoDelay() {

         throw new IllegalStateException(NOT_SUPPORTED);

     }

     @Override

     public void setTcpNoDelay(boolean tcpNoDelay) {

         throw new IllegalStateException(NOT_SUPPORTED);

     }

     @Override

     public int getLinger() {

        throw new IllegalStateException(NOT_SUPPORTED);

     }

     @Override

     public void setLinger(int linger) {

         throw new IllegalStateException(NOT_SUPPORTED);

     }    

     @Override

     public int getSocketTimeout() {

         throw new IllegalStateException(NOT_SUPPORTED);

     }

     @Override

     public void setSocketTimeout(int socketTimeout) {

         throw new IllegalStateException(NOT_SUPPORTED);

     }    

     @Override

     public void closeChannel(SelectableChannel channel) {

         try{

             channel.close();

         } catch (IOException ex){

             ; // LOG ME

         }

         if (asyncQueueReader != null) {

             asyncQueueReader.onClose(channel);

         }

         if (asyncQueueWriter != null) {

             asyncQueueWriter.onClose(channel);

         }

     }

     //--------------- ConnectorInstanceHandler -----------------------------

     @Override

     protected Callable<ConnectorHandler> getConnectorInstanceHandlerDelegate() {

         return new Callable<ConnectorHandler>() {

             public ConnectorHandler call() throws Exception {

                 return new UDPConnectorHandler();

             }

         };

     }

 }