message_transport_common: subscriber

00001 #ifndef MESSAGE_TRANSPORT_SUBSCRIBER_IMPL_H
00002 #define MESSAGE_TRANSPORT_SUBSCRIBER_IMPL_H
00003 
00004 /*********************************************************************
00005 * Software License Agreement (BSD License)
00006 * 
00007 *  Copyright (c) 2009, Willow Garage, Inc.
00008 *  All rights reserved.
00009 * 
00010 *  Redistribution and use in source and binary forms, with or without
00011 *  modification, are permitted provided that the following conditions
00012 *  are met:
00013 * 
00014 *   * Redistributions of source code must retain the above copyright
00015 *     notice, this list of conditions and the following disclaimer.
00016 *   * Redistributions in binary form must reproduce the above
00017 *     copyright notice, this list of conditions and the following
00018 *     disclaimer in the documentation and/or other materials provided
00019 *     with the distribution.
00020 *   * Neither the name of the Willow Garage nor the names of its
00021 *     contributors may be used to endorse or promote products derived
00022 *     from this software without specific prior written permission.
00023 * 
00024 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00025 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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00037 
00038 #include "message_transport/subscriber_plugin.h"
00039 #include <pluginlib/class_loader.h>
00040 #include <boost/scoped_ptr.hpp>
00041 
00042 namespace message_transport {
00043 
00044         class  SubscriberImplGen
00045         {
00046                 public :
00047                         SubscriberImplGen() : unsubscribed_(false) { }
00048 
00049                         ~SubscriberImplGen()
00050                         {
00051                         }
00052 
00053                         bool isValid() const
00054                         {
00055                                 return !unsubscribed_;
00056                         }
00057 
00058                         virtual void reset(const TransportHints& transport_hints) = 0;
00059                         void shutdown() {
00060                                 this->shutdownImpl();
00061                         }
00062                         virtual void shutdownImpl() = 0;
00063                         virtual SubscriberPluginGen * getSubscriber() = 0;
00064 
00065                         template <class M> 
00066                                 SubscriberPlugin<M> * getTemplateSubscriber() {
00067                                         return dynamic_cast<SubscriberPlugin<M>*>(getSubscriber());
00068                                 }
00069 
00070 
00071                         virtual std::vector<std::string> getDeclaredClasses() = 0;
00072                 protected :
00073 
00074                         bool unsubscribed_;
00075         };
00076 
00077         template <class M>
00078                 class  SubscriberImpl : public SubscriberImplGen
00079         {
00080                 public:
00081                         SubscriberImpl(const std::string & packageName,const std::string & className)
00082                                 : loader_(packageName, 
00083                                                 std::string("message_transport::SubscriberPlugin<")+className+">"),
00084                                 subscriber_(NULL) { }
00085 
00086                         ~SubscriberImpl() {
00087                                 shutdownImpl();
00088                                 delete subscriber_; 
00089                         }
00090 
00091                         virtual void shutdownImpl()
00092                         {
00093                                 if (!unsubscribed_) {
00094                                         unsubscribed_ = true;
00095                                         subscriber_->shutdown();
00096                                 }
00097                         }
00098 
00099                         virtual void reset(const TransportHints& transport_hints) {
00100                                 std::string lookup_name = SubscriberPluginGen::getLookupName(transport_hints.getTransport());
00101                                 delete subscriber_;
00102                                 subscriber_ = loader_.createClassInstance(lookup_name);
00103                         }
00104 
00105                         virtual SubscriberPluginGen * getSubscriber() {
00106                                 return subscriber_;
00107                         }
00108 
00109                         virtual std::vector<std::string> getDeclaredClasses() {
00110                                 return loader_.getDeclaredClasses();
00111                         }
00112 
00113                 protected:
00114 
00115                         pluginlib::ClassLoader< SubscriberPlugin<M> > loader_;
00116                         SubscriberPlugin<M>* subscriber_;
00117         };
00118 };
00119 
00120 #endif // MESSAGE_TRANSPORT_SUBSCRIBER_IMPL_H
subscriber_impl.h
