Re: [Boost-users] Boost Serialization - Base Classes (very confused)

Subject: Re: [Boost-users] Boost Serialization - Base Classes (very confused)
From: Robert Ramey (ramey_at_[hidden])
Date: 2009-03-19 13:02:59

See below.

Robert Ramey

Adrien Guillon wrote:
> Hi all,
>
> I don't understand why the following code does not work.  I get an
> unregistered class exception.
>
> AJ
>
>
> #include <boost/serialization/serialization.hpp>
> #include <boost/archive/text_oarchive.hpp>
> #include <boost/archive/text_iarchive.hpp>
> #include <boost/serialization/export.hpp>
>
> #include <string>
> #include <sstream>
> #include <iostream>
>
> namespace pbb { // BEGIN NAMESPACE pbb
> namespace internal { // BEGIN NAMESPACE internal
>
> /**
> * The base class for all requests to be made of a server.
> */
> class server_request
> {
>    friend class boost::serialization::access;
> public:
>    virtual ~server_request();
>    virtual std::string description() = 0;
> private:
>    template <typename Archive>
>    void serialize(Archive& ar, const unsigned int version)
>    {
>    }
> };
>
> class hello_request : public server_request
> {
>    friend class boost::serialization::access;
> public:
>    virtual ~hello_request();
>    virtual std::string description();
> private:
>    template <typename Archive>
>    void serialize(Archive& ar, const unsigned int version)
>    {
>        ar & boost::serialization::base_object<server_request>(*this);
>    }
> };
>
> } // END NAMESPACE internal
> } // END NAMESPACE pbb
>
>
> namespace pbb { // BEGIN NAMESPACE pbb
> namespace internal { // BEGIN NAMESPACE internal
>
>
> server_request::~server_request()
> {
> }
>
> hello_request::~hello_request()
> {
> }
>
> std::string hello_request::description()
> {
>    return "HELLO REQUEST";
> }
>
> } // END NAMESPACE internal
> } // END NAMESPACE pbb
>
>
> BOOST_CLASS_EXPORT(pbb::internal::server_request);
> BOOST_CLASS_EXPORT(pbb::internal::hello_request);
>
> void msave(const pbb::internal::server_request& request,
> boost::archive::text_oarchive& o)
> {
>    o << request;
> }
>
> pbb::internal::server_request* mload(boost::archive::text_iarchive&
> in) {
>    pbb::internal::server_request* r;
>    in >> r;
>    return r;
> }
>
>
> int main()
> {
>
>    // Create a string stream for I/O
>    std::stringstream stream;
>
>    pbb::internal::server_request* request = new
> pbb::internal::hello_request();
>
>    // Write a server request
> {
>
>    boost::archive::text_oarchive out_archive(stream);
>    //msave(*request, out_archive); // uh oh - throwing away "pointerness"
      out_archve << request;
> }
>
>    // Read a server request
>    pbb::internal::server_request* incoming_request;>
> {
>    boost::archive::text_iarchive in_archive(stream);
>    incoming_request = mload(in_archive); // preserve symetry
      in_archve >> incoming request
> }
>
>    std::cout << incoming_request->description() << std::endl;
>
>
>
> }