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

Subject: Re: [Boost-users] Serialization of a std::vector< boost::shared_ptr< A> > throws unregistered_class exception
From: Robert Ramey (ramey_at_[hidden])
Date: 2009-03-19 12:58:57

Depending on which version of boost you're using. You may have
to include a special macro - look into serialization/shared_ptr.hpp
at the end.

Robert Ramey

Benoit Gagnon wrote:
> 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?