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 package com.sun.grizzly.connectioncache.client;

 import com.sun.grizzly.CallbackHandler;

 import com.sun.grizzly.ConnectorHandler;

 import com.sun.grizzly.Context;

 import com.sun.grizzly.Controller;

 import com.sun.grizzly.Controller.Protocol;

 import com.sun.grizzly.IOEvent;

 import com.sun.grizzly.SelectorHandler;

 import com.sun.grizzly.connectioncache.spi.transport.ContactInfo;

 import java.io.IOException;

 import java.net.SocketAddress;

 import java.nio.ByteBuffer;

 import java.nio.channels.ClosedChannelException;

 import java.nio.channels.SelectableChannel;

 import java.nio.channels.SelectionKey;

 import java.nio.channels.Selector;

 /**

  * Extended implementation of the DefaultSelectionKeyHandler with

  * ConnectionManagement integrated in it

  *

  * @author Alexey Stashok

  */

 public class CacheableConnectorHandler implements ConnectorHandler<SelectorHandler, CallbackHandler>,

         ContactInfo<ConnectorHandler>, CallbackHandler {

     private SocketAddress targetAddress;

     private Protocol protocol;

     private SelectorHandler selectorHandler;

     private CacheableConnectorHandlerPool parentPool;

     private ConnectorHandler underlyingConnectorHandler;

     private CallbackHandler underlyingCallbackHandler;

     private ConnectExecutor connectExecutor;

     public CacheableConnectorHandler(CacheableConnectorHandlerPool parentPool) {

         this.parentPool = parentPool;

         connectExecutor = new ConnectExecutor();

     }

     void setProtocol(Protocol protocol) {

         this.protocol = protocol;

     }

     public Protocol protocol() {

         return protocol;

     }

     // connect method #1

     public void connect(SocketAddress remoteAddress, CallbackHandler callbackHandler, SelectorHandler selectorHandler) throws IOException {

         connectExecutor.setParameters(remoteAddress, callbackHandler, selectorHandler);

         doConnect(remoteAddress);

     }

     // connect method #2

     public void connect(SocketAddress remoteAddress, CallbackHandler callbackHandler) throws IOException {

         connectExecutor.setParameters(remoteAddress, callbackHandler);

         doConnect(remoteAddress);

     }

     // connect method #3

     public void connect(SocketAddress remoteAddress) throws IOException {

         connectExecutor.setParameters(remoteAddress);

         doConnect(remoteAddress);

     }

     // connect method #4

     public void connect(SocketAddress remoteAddress, SocketAddress localAddress,

             CallbackHandler callbackHandler, SelectorHandler selectorHandler) throws IOException {

         connectExecutor.setParameters(remoteAddress, localAddress, callbackHandler, selectorHandler);

         doConnect(remoteAddress);

     }

     // connect method #5

     public void connect(SocketAddress remoteAddress, SocketAddress localAddress, CallbackHandler callbackHandler) throws IOException {

         connectExecutor.setParameters(remoteAddress, localAddress, callbackHandler);

         doConnect(remoteAddress);

     }

     // connect method #6

     public void connect(SocketAddress remoteAddress, SocketAddress localAddress) throws IOException {

         connectExecutor.setParameters(remoteAddress, localAddress);

         doConnect(remoteAddress);

     }

     /**

      * Releases underlying connection, which means it could be reused for writing

      * by other <code>CacheableConnectorHandler</code>, however this 

      * <code>CacheableConnectorHandler</code> will be still interested in getting 

      * expectedResponseCount responses on it.

      * 

      * @param expectedResponseCount number of reponses expected on the connection

      */

     public void release(int expectedResponseCount) {

         parentPool.getOutboundConnectionCache().release(underlyingConnectorHandler, expectedResponseCount);

     }

     /**

      * Notifies connection cache, that response was received. And connection cache

      * could decrease expected response counter by 1

      */

     public void responseReceived() {

         parentPool.getOutboundConnectionCache().responseReceived(underlyingConnectorHandler);

     }

     /**

      * @param targetAddress target connection address

      * @throws java.io.IOException if IO error happened

      */

     private void doConnect(SocketAddress targetAddress) throws IOException {

         this.targetAddress = targetAddress;

         selectorHandler = connectExecutor.selectorHandler;

         underlyingCallbackHandler = connectExecutor.callbackHandler;

         underlyingConnectorHandler = parentPool.

                 getOutboundConnectionCache().get(this, parentPool.getConnectionFinder());

         /* check whether NEW connection was created, or taken from cache */

         if (!connectExecutor.wasCalled()) { // if taken from cache

             //if connection is taken from cache - explicitly notify callback handler

             underlyingConnectorHandler.setCallbackHandler(this);

             notifyCallbackHandlerPseudoConnect();

         }

     }

     public void close() throws IOException {

         parentPool.getOutboundConnectionCache().release(underlyingConnectorHandler, 0);

     }

     public long read(ByteBuffer byteBuffer, boolean blocking) throws IOException {

         return underlyingConnectorHandler.read(byteBuffer, blocking);

     }

     public long write(ByteBuffer byteBuffer, boolean blocking) throws IOException {

         return underlyingConnectorHandler.write(byteBuffer, blocking);

     }

     public void finishConnect(SelectionKey key) {

         // Call underlying finishConnect only if connection was just established

         if (connectExecutor.wasCalled()) {

             try{

                 underlyingConnectorHandler.finishConnect(key);

             } catch (IOException ex){

                 Controller.logger().severe(ex.getMessage());

             }

         }

     }

     public void setController(Controller controller) {

         underlyingConnectorHandler.setController(controller);

     }

     public Controller getController() {

         return underlyingConnectorHandler.getController();

     }

     public SelectableChannel getUnderlyingChannel() {

         return underlyingConnectorHandler.getUnderlyingChannel();

     }

     public CallbackHandler getCallbackHandler() {

         return underlyingConnectorHandler.getCallbackHandler();

     }

     public void setCallbackHandler(CallbackHandler callbackHandler) {

         underlyingConnectorHandler.setCallbackHandler(callbackHandler);

     }

     public SelectorHandler getSelectorHandler() {

         return underlyingConnectorHandler.getSelectorHandler();

     }

     //---------------------- ContactInfo implementation --------------------------------

     public ConnectorHandler createConnection() throws IOException {

         underlyingConnectorHandler = parentPool.getProtocolConnectorHandlerPool().acquireConnectorHandler(protocol);

         connectExecutor.setConnectorHandler(underlyingConnectorHandler);

         connectExecutor.invokeProtocolConnect();

         return underlyingConnectorHandler;

     }

     @Override

     public String toString() {

         StringBuffer sb = new StringBuffer();

         sb.append(getClass().getName());

         sb.append(" targetAddress: ");

         sb.append(targetAddress);

         sb.append(" protocol: ");

         sb.append(protocol);

         sb.append(" hashCode: ");

         sb.append(super.hashCode());

         return sb.toString();

     }

     //----- Override hashCode(), equals() as part of ContactInfo implementation -----------

     @Override

     public int hashCode() {

         return targetAddress.hashCode() ^ protocol.hashCode();

     }

     @Override

     public boolean equals(Object o) {

         if (o instanceof CacheableConnectorHandler) {

             CacheableConnectorHandler handler = (CacheableConnectorHandler) o;

             if (selectorHandler == null || handler.selectorHandler == null) {

                 return targetAddress.equals(handler.targetAddress) &&

                         protocol.equals(handler.protocol);

             } else {

                 return targetAddress.equals(handler.targetAddress) &&

                         protocol.equals(handler.protocol) &&

                         selectorHandler == handler.selectorHandler;

             }

         }

         return false;

     }

     private void notifyCallbackHandlerPseudoConnect() throws ClosedChannelException {

         Selector protocolSelector = underlyingConnectorHandler.getSelectorHandler().getSelector();

         SelectionKey key = underlyingConnectorHandler.getUnderlyingChannel().keyFor(protocolSelector);

         if (key == null) {

             // Register channel on selector

             key = underlyingConnectorHandler.getUnderlyingChannel().

                     register(protocolSelector, SelectionKey.OP_CONNECT);

         }

         assert key != null;

         final Context context = parentPool.getController().pollContext(key);

         onConnect(new IOEvent.DefaultIOEvent<Context>(context));

     }

     //---------------------- CallbackHandler implementation --------------------------------

     public void onConnect(IOEvent ioEvent) {

         if (underlyingCallbackHandler == null) {

             underlyingCallbackHandler = new CallbackHandler<Context>(){

                 public void onConnect(IOEvent<Context> ioEvent) {

                     SelectionKey key = ioEvent.attachment().getSelectionKey();

                     finishConnect(key);

                     getController().registerKey(key,SelectionKey.OP_WRITE,

                             protocol);

                 }

                 public void onRead(IOEvent<Context> ioEvent) {}

                 public void onWrite(IOEvent<Context> ioEvent) {}

             };

         }

         underlyingCallbackHandler.onConnect(ioEvent);

     }

     public void onRead(IOEvent ioEvent) {

         underlyingCallbackHandler.onRead(ioEvent);

     }

     public void onWrite(IOEvent ioEvent) {

         underlyingCallbackHandler.onWrite(ioEvent);

     }

     /**

      * Class is responsible for execution corresponding

      * underlying {@link ConnectorHandler} connect method

      */

     private class ConnectExecutor {

         private int methodNumber;

         private ConnectorHandler connectorHandler;

         private SocketAddress remoteAddress;

         private SocketAddress localAddress;

         private SelectorHandler selectorHandler;

         private CallbackHandler callbackHandler;

         private boolean wasCalled;

         public void setConnectorHandler(ConnectorHandler connectorHandler) {

             this.connectorHandler = connectorHandler;

         }

         public void setParameters(SocketAddress remoteAddress, CallbackHandler callbackHandler, SelectorHandler selectorHandler) {

             setParameters(remoteAddress, null, callbackHandler, selectorHandler);

             methodNumber = 1;

         }

         public void setParameters(SocketAddress remoteAddress, CallbackHandler callbackHandler) {

             setParameters(remoteAddress, null, callbackHandler);

             methodNumber = 2;

         }

         public void setParameters(SocketAddress remoteAddress) {

             setParameters(remoteAddress, (SocketAddress) null);

             methodNumber = 3;

         }

         public void setParameters(SocketAddress remoteAddress, SocketAddress localAddress, CallbackHandler callbackHandler,SelectorHandler selectorHandler) {

             wasCalled = false;

             this.remoteAddress = remoteAddress;

             this.localAddress = localAddress;

             this.callbackHandler = callbackHandler;

             this.selectorHandler = selectorHandler;

             methodNumber = 4;

         }

         public void setParameters(SocketAddress remoteAddress, SocketAddress localAddress, CallbackHandler callbackHandler) {

             setParameters(remoteAddress, localAddress, callbackHandler , null);

             methodNumber = 5;

         }

         public void setParameters(SocketAddress remoteAddress, SocketAddress localAddress) {

             setParameters(remoteAddress, localAddress, null);

             methodNumber = 6;

         }

         public boolean wasCalled() {

             return wasCalled;

         }

         public void invokeProtocolConnect() throws IOException {

             wasCalled = true;

             switch(methodNumber) {

             case 1: connectorHandler.connect(remoteAddress, CacheableConnectorHandler.this, selectorHandler);

             break;

             case 2:

             case 3: connectorHandler.connect(remoteAddress, CacheableConnectorHandler.this);

             break;

             case 4: connectorHandler.connect(remoteAddress, localAddress, CacheableConnectorHandler.this, selectorHandler);

             break;

             case 5:

             case 6: connectorHandler.connect(remoteAddress, localAddress, CacheableConnectorHandler.this);

             break;

             default: throw new IllegalStateException("Can not find appropriate connect method: " + methodNumber);

             }

         }

     }

 }