Re: [Boost-users] Boost.Serialization: Restoringobjectstate(preventcreation of a new object)?

Subject: Re: [Boost-users] Boost.Serialization: Restoringobjectstate(preventcreation of a new object)?
From: ray_at_[hidden]
Date: 2010-09-01 05:11:03

I've ended up with the following solution:

#include <fstream>
#include <iostream>
#include <boost/archive/xml_iarchive.hpp>
#include <boost/archive/xml_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>
#include <boost/serialization/export.hpp>
#include <boost/foreach.hpp>

#define _SERIALIZATION_FUNC(CLASS_NAME, ARCH_TYPE) \
public: \
    virtual void Serialize(ARCH_TYPE& ar) \
{ \
    CLASS_NAME& x = *static_cast<CLASS_NAME*>(this); \
    ar & BOOST_SERIALIZATION_NVP(x); \
}

#define SERIALIZATION(CLASS_NAME) \
public: \
    _SERIALIZATION_FUNC(CLASS_NAME, boost::archive::text_iarchive) \
    _SERIALIZATION_FUNC(CLASS_NAME, boost::archive::text_oarchive) \
    _SERIALIZATION_FUNC(CLASS_NAME, boost::archive::xml_iarchive) \
    _SERIALIZATION_FUNC(CLASS_NAME, boost::archive::xml_oarchive) \
private: \
    friend class boost::serialization::access; \
    template<typename TArchive> \
    void serialize(TArchive & ar, const unsigned int version /*file_version*/)

class A
{
public:
    A() : m_a(0) {}

protected:
    int m_a;

private:
    SERIALIZATION(A)
    {
        ar & BOOST_SERIALIZATION_NVP(m_a);
    }
};

class B : public A
{
public:
    B() : m_b(0) {}

protected:
    int m_b;

private:
    SERIALIZATION(B)
    {
        ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(A);
        ar & BOOST_SERIALIZATION_NVP(m_b);
    }
};
BOOST_CLASS_EXPORT(B)

int main(int argc, char* argv[])
{
    // ...
    A a;
    B b;
    std::list<A*> lst;        // List of A* pointers
    lst.push_back(&a);        // Base class
    lst.push_back(&b);        // Derived

    //...
    // Save
    {
        std::ofstream ofs("c:/test.xml");
        boost::archive::xml_oarchive oa(ofs);
        BOOST_FOREACH(A* pA, lst)       
        {
            pA->Serialize(oa);
        }
    }

    //...
    // Restore
    {
        std::ifstream is("c:/test.xml");
        boost::archive::xml_iarchive ia(is);
        BOOST_FOREACH(A* pA, lst )       
        {
            pA->Serialize(ia);
        }
    }

    //...
}

Everything works as expected (my classes can live with a few additional virtual functions :). And thank you for creating this excellent serialization library!
Ray