##### Coverage Report - com.sun.grizzly.connectioncache.spi.transport.OutboundConnectionCache

Classes in this File | Line Coverage | Branch Coverage | Complexity
OutboundConnectionCache |
N/A | N/A
N/A | N/A
| 0.0;0

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     /*
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      *
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      * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
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      *
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      * Copyright 2007-2008 Sun Microsystems, Inc. All rights reserved.
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      *
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      * The contents of this file are subject to the terms of either the GNU
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      * General Public License Version 2 only ("GPL") or the Common Development
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      * and Distribution License("CDDL") (collectively, the "License").  You
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      * may not use this file except in compliance with the License. You can obtain
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      * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
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      * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
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      * language governing permissions and limitations under the License.
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      *
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      * When distributing the software, include this License Header Notice in each
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      * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
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      * Sun designates this particular file as subject to the "Classpath" exception
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      * as provided by Sun in the GPL Version 2 section of the License file that
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      * accompanied this code.  If applicable, add the following below the License
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      * Header, with the fields enclosed by brackets [] replaced by your own
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      * identifying information: "Portions Copyrighted [year]
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      * [name of copyright owner]"
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      *
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      * Contributor(s):
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      *
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      * If you wish your version of this file to be governed by only the CDDL or
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      * only the GPL Version 2, indicate your decision by adding "[Contributor]
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      * elects to include this software in this distribution under the [CDDL or GPL
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      * Version 2] license."  If you don't indicate a single choice of license, a
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      * recipient has the option to distribute your version of this file under
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      * either the CDDL, the GPL Version 2 or to extend the choice of license to
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      * its licensees as provided above.  However, if you add GPL Version 2 code
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      * and therefore, elected the GPL Version 2 license, then the option applies
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      * only if the new code is made subject to such option by the copyright
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      * holder.
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      *
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      */
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     package com.sun.grizzly.connectioncache.spi.transport;
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     import java.io.Closeable;
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     import java.io.IOException ;
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     /** A concurrent mostly non-blocking connection cache.  Here a Connection is an
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      * abstraction of a Socket or SocketChannel: basically some sort of resource
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      * that is expensive to acquire, and can be re-used freely.  The cache
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      * maintains a loose upper bound on the number of cached connections, and
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      * reclaims connections as needed.
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      * <P>
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      * This cache places minimal requirements on the Connections that it contains:
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      * <ol>
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      * <li>A Connection must implement a close() method.  This is called when idle
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      * connections are reclaimed.
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      * <li>A Connection must be usable as a HashMap key.
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      * <li>There must be a ContactInfo class that is used to create Connection
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      * instances.  The ContactInfo class must support a create() method that
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      * returns a Connection.
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      * <li>The ContactInfo must be usable as a HashMap key.
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      * <li>All instances created from a ContactInfo are equal; that is, any request
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      * sent to a particular ContactInfo can used an instance created from that
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      * ContactInfo.  For example, in the CORBA case, IP host and port is not always
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      * sufficient: we may also need the Codeset type that indicates how Strings are
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      * encoded.  Basically, protocols (like GIOP) that bind session state to a
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      * Connection may need more than transport information in the ContactInfo.
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      * </ol>
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      * <P>
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      * Some simple methods are provided for monitoring the state of the cache:
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      * numbers of busy and idle connections, and the total number of connections in
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      * the cache.
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      *
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      * @param C a connection
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      */
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     public interface OutboundConnectionCache<C extends Closeable>
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         extends ConnectionCache<C> {
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         /** Configured maximum number of connections supported per ContactInfo.
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          * @return  maximum number of connections supported per <code>ContactInfo</code>
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          */
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         int maxParallelConnections() ;
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         /** Determine whether a new connection could be created by the
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          * ConnectionCache or not.
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          * @param cinfo  a <code>ContactInfo</code>
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          * @return  true if new connection could be created by {@link ConnectionCache}, otherwise false.
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          */
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         boolean canCreateNewConnection( ContactInfo<C> cinfo ) ;
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         /** Return a Connection corresponding to the given ContactInfo.
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          * This works as follows:
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          * <ul>
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          * <li>Call the finder.  If it returns non-null, use that connection;
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          * (Note that this may be a new connection, created in the finder)
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          * <li>otherwise, Use an idle connection, if one is available;
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          * <li>otherwise, create a new connection, if not too many connections are
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          * open;
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          * <li>otherwise, use a busy connection.
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          * </ul>
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          * Note that creating a new connection requires EITHER:
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          * <ul>
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          * <li>there is no existing connection for the ContactInfo
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          * <li> OR the total number of connections in the cache is less than the
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          * HighWaterMark and the number of connections for this ContactInfo
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          * is less than MaxParallelConnections.
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          * </ul>
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          * We will always return a
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          * Connection for a get call UNLESS we have no existing connection and
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          * an attempt to create a new connection fails.  In this case, the
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          * IOException thrown by ContactInfo.create is propagated out of this
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          * method.
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          * <P>
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          * It is possible that the cache contains connections that no longer connect
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          * to their destination.  In this case, it is the responsibility of the
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          * client of the cache to close the broken connection as they are detected.
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          * Connection reclamation may also handle the cleanup, but note that a
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          * broken connection with pending responses will never be reclaimed.
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          * <P>
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          * Note that the idle and busy connection collections that are
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          * passed to the finder are unmodifiable collections.  They have iterators
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          * that return connections in LRU order, with the least recently used
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          * connection first.  This is done to aid a finder that wishes to consider
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          * load balancing in its determination of an appropriate connection.
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          * <P>
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          * @param cinfo  a <code>ContactInfo</code>
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          * @param finder  a <code>ConnectionFinder</code>
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          * @return  a connection
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          * @throws java.io.IOException
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          */
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         C get( ContactInfo<C> cinfo, ConnectionFinder<C> finder
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             ) throws IOException ;
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         /** Behaves the same as get( ContactInfo<C>, ConnectionFinder<C> )
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          * except that no connection finder is provided, so that step is
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          * ignored.
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          * @param cinfo  a <code>ContactInfo</code>
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          * @return  a connection
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          * @throws java.io.IOException
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          */
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         C get( ContactInfo<C> cinfo ) throws IOException ;
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         /** Release a Connection previously obtained from get.  Connections that
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          * have been released as many times as they have been returned by
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          * get are idle; otherwise a Connection is busy.  Some number of
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          * responses (usually 0 or 1) may be expected ON THE SAME CONNECTION
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          * even for an idle connection.  We maintain a count of the number of
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          * outstanding responses we expect for protocols that return the response
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          * on the same connection on which the request was received.  This is
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          * necessary to prevent reclamation of a Connection that is idle, but
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          * still needed to send responses to old requests.
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          * @param conn  a connection
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          * @param numResponseExpected  number of connections in which a response is expected
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          */
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         void release( C conn, int numResponseExpected ) ;
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         /** Inform the cache that a response has been received on a particular
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          * connection.  This must also be called in the event that no response
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          * is received, but the client times out waiting for a response, and
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          * decides to abandon the request.
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          * <P>
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          * When a Connection is idle, and has no pending responses, it is
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          * eligible for reclamation.
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          * @param conn  a connection
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          */
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         void responseReceived( C conn ) ;
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     }