[Boost-users] Serialization of a std::vector< boost::shared_ptr< A > > throws unregistered_class exception

Subject: [Boost-users] Serialization of a std::vector< boost::shared_ptr< A > > throws unregistered_class exception
From: Benoit Gagnon (b.gagnon_at_[hidden])
Date: 2009-03-18 20:46:09

Given the following classes:

   class Building { ... };
   class House : public Building { ... };
   class Hospital : public Building { ... };

With appropriate serialization method templates such as:

   class House: public Building {
   friend class boost::serialization::access;
   template<class Archive>
   void serialize(Archive& ar, const unsigned int version ) {
       ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP( Building );
       ar & BOOST_SERIALIZATION_NVP( mNumBedrooms );
       ar & BOOST_SERIALIZATION_NVP( mNumBathrooms );
   }
   ...

I have the following registrations in main.cpp where the archiving/
restoring is performed:

   BOOST_SERIALIZATION_SHARED_PTR( Building )
   BOOST_SERIALIZATION_SHARED_PTR( House )
   BOOST_SERIALIZATION_SHARED_PTR( Hospital )

In main.ccp, I would like to serialize a std::vector<
boost::shared_ptr< Building > > object.
Like this:

   std::vector< boost::shared_ptr< Building > > buildings;
   ...
   std::ofstream ofs( "archive.txt" );
   boost::archive::text_oarchive oa( ofs );
   oa & BOOST_SERIALIZATION_NVP( buildings );

This compiles correctly but fails at runtime with a
"unregistered_class" exception. The individual classes (Building,
House, Hospital) can be serialized and restored fine individually.
That is true for objects, pointers and shared_ptr. A vector of plain
pointers to any of those types also works fine. But a vector of
shared_ptr to any of those types fails at runtime..

What kind of registration must be done to achieve this?