1 /*
   2  * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package com.sun.nio.sctp;
  26 
  27 /**
  28  * A skeletal handler that consumes notifications and continues.
  29  *
  30  * <P> This class trivially implements the {@code handleNotification} methods to
  31  * return {@link HandlerResult#CONTINUE CONTINUE} so that all notifications are
  32  * consumed and the channel continues to try and receive a message.
  33  *
  34  * <P> It also provides overloaded versions of the {@code handleNotification}
  35  * methods, one for each of the required supported notification types, {@link
  36  * AssociationChangeNotification}, {@link PeerAddressChangeNotification},
  37  * {@link SendFailedNotification}, and {@link ShutdownNotification}. The
  38  * appropriate method will be invoked when the notification is received.
  39  *
  40  * @since 1.7
  41  */
  42 public class AbstractNotificationHandler<T>
  43     implements NotificationHandler<T>
  44 {
  45     /**
  46      * Initializes a new instance of this class.
  47      */
  48     protected AbstractNotificationHandler() {}
  49 
  50     /**
  51      * Invoked when an implementation specific notification is received from the
  52      * SCTP stack.
  53      *
  54      * @param  notification
  55      *         The notification
  56      *
  57      * @param  attachment
  58      *         The object attached to the {@code receive} operation when it was
  59      *         initiated.
  60      *
  61      * @return  The handler result
  62      */
  63     @Override
  64     public HandlerResult handleNotification(Notification notification,
  65                                             T attachment) {
  66         return HandlerResult.CONTINUE;
  67     }
  68 
  69     /**
  70      * Invoked when an {@link AssociationChangeNotification} is received from
  71      * the SCTP stack.
  72      *
  73      * @param  notification
  74      *         The notification
  75      *
  76      * @param  attachment
  77      *         The object attached to the {@code receive} operation when it was
  78      *         initiated.
  79      *
  80      * @return  The handler result
  81      */
  82     public HandlerResult handleNotification(AssociationChangeNotification notification,
  83                                             T attachment) {
  84         return HandlerResult.CONTINUE;
  85     }
  86 
  87     /**
  88      * Invoked when an {@link PeerAddressChangeNotification} is received from
  89      * the SCTP stack.
  90      *
  91      * @param  notification
  92      *         The notification
  93      *
  94      * @param  attachment
  95      *         The object attached to the {@code receive} operation when it was
  96      *         initiated.
  97      *
  98      * @return  The handler result
  99      */
 100     public HandlerResult handleNotification(PeerAddressChangeNotification notification,
 101                                             T attachment) {
 102         return HandlerResult.CONTINUE;
 103     }
 104 
 105     /**
 106      * Invoked when an {@link SendFailedNotification} is received from
 107      * the SCTP stack.
 108      *
 109      * @param  notification
 110      *         The notification
 111      *
 112      * @param  attachment
 113      *         The object attached to the {@code receive} operation when it was
 114      *         initiated.
 115      *
 116      * @return  The handler result
 117      */
 118     public HandlerResult handleNotification(SendFailedNotification notification,
 119                                             T attachment) {
 120         return HandlerResult.CONTINUE;
 121     }
 122 
 123     /**
 124      * Invoked when an {@link ShutdownNotification} is received from
 125      * the SCTP stack.
 126      *
 127      * @param  notification
 128      *         The notification
 129      *
 130      * @param  attachment
 131      *         The object attached to the {@code receive} operation when it was
 132      *         initiated.
 133      *
 134      * @return  The handler result
 135      */
 136     public HandlerResult handleNotification(ShutdownNotification notification,
 137                                             T attachment) {
 138         return HandlerResult.CONTINUE;
 139     }
 140 }