Re: [Boost-users] Serialization of pointers ?-->loadingnotworking...

20 Jan 2010

      So I resolved the problem using const !
I post as it may be profitable to someone else ...

It is only needed to split the serialize function into save and load 
functions and then to const_cast the Sensor

Here is the code:

#include <iostream>
#include <iterator>
#include <algorithm>

#include <sstream>
#include <fstream>
#include <vector>

#include <boost/archive/text_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>
#include <boost/serialization/string.hpp>
#include <boost/serialization/split_member.hpp>

using namespace std;
using namespace boost::archive;
using namespace boost::serialization;

/*
 * Class Sensor
 *
 */
class Sensor{
    public:
        Sensor(const std::string& name="");
        virtual ~Sensor();
        inline std::string getName() const {return m_name;}
        inline void setName(const std::string& name) {m_name=name;}

    protected:
        std::string m_name;

    private:
        friend class boost::serialization::access;
        template <class Archive> void serialize(Archive& ar, const unsigned 
int version){
            cout << "Serialization of Sensor" << endl;
            ar & m_name;
        }
};

Sensor::Sensor(const std::string& name){
    m_name=name;
}

Sensor::~Sensor(){
}

/*
 * Class SensorReading
 *
 */
class SensorReading{
    public:
        SensorReading(const Sensor* s=0, double time=0);
        virtual ~SensorReading();
        inline double getTime() const {return m_time;}
        inline void setTime(double t) {m_time=t;}
        inline const Sensor* getSensor() const {return m_sensor;}
        inline void print(){
            cout << "SensorReading: " << "(" << m_time << "," << 
m_sensor->getName() << ")" << endl;
        }

    protected:
        double m_time;
        const Sensor* m_sensor;

    private:
        friend class boost::serialization::access;
        template <class Archive> void save(Archive& ar, const unsigned int 
version)const{
            cout << "Serialization of SensorReading" << endl;
            ar << m_time;
            ar << m_sensor;
        }
        template <class Archive> void load(Archive& ar, const unsigned int 
version){
            cout << "Deserialization of SensorReading" << endl;
            ar >> m_time;
            ar >> const_cast<Sensor*&>(m_sensor);
        }
        template <class Archive> void serialize(Archive& ar, const unsigned 
int version){
            boost::serialization::split_member(ar, *this, version);
        }
};

SensorReading::SensorReading(const Sensor* s, double t){
    m_sensor=s;
    m_time=t;
}

SensorReading::~SensorReading(){}

/*
 * Class SensorReading
 *
 */

template <class A> void saveIntoFileSens(SensorReading& sr, const char* 
file){
        ofstream ofile(file);
        A ar(ofile);
        ar << sr;
        ofile.close();
}

template <class A> void loadFromFileSens(SensorReading& sr, const char* 
file){
    ifstream ifile(file);
    A ar(ifile);
    ar >> sr;
    ifile.close();
}

/*
 * MAIN
 *
 */
int main(){

    const Sensor s = Sensor("SensorNom");
    SensorReading sr = SensorReading(&s,67);

    sr.print();
    saveIntoFileSens<text_oarchive>(sr, "out.txt");
    SensorReading sr2;
    loadFromFileSens<text_iarchive>(sr2, "out.txt");
    sr2.print();

    cout << "end" << endl;

    return 0;
}

----- Original Message ----- 
From: "Simon Ruffieux" <simon.ruffieux@gmail.com>
Newsgroups: gmane.comp.lib.boost.user
To: <boost-users@lists.boost.org>
Sent: Friday, January 15, 2010 9:54 AM
Subject: Re: Serialization of pointers ?-->loadingnotworking...
...
Hum hum ...
The problem was that my Sensor pointer contained in the class 
SensorReading was declared const:
class SensorReading{
   public:
       SensorReading(const Sensor* s=0, double time=0);
       virtual ~SensorReading();
protected:
       double m_time;
       const Sensor* m_sensor;
};
If I do not declare it as Sensor* m_sensor; And correct accordingly the 
different functions prototypes. Then it works.
However I was wondering if there were anyway of serializing it while 
keeping it const ?
Thansk
----- Original Message ----- 
From: "Simon Ruffieux" <simon.ruffieux@gmail.com>
Newsgroups: gmane.comp.lib.boost.user
To: <boost-users@lists.boost.org>
Sent: Friday, January 15, 2010 9:22 AM
Subject: Re: Serialization of pointers ? -->loadingnotworking...
...
I should maybe have attached with the message this more reduced code 
containing only the problematic classes.
This code fails as previously said during compilation because of the 
"loadFromFileSens"
CODE
/*
* SensorReading
*
*/
class Sensor{
   public:
       Sensor(const std::string& name="");
       virtual ~Sensor();
       inline std::string getName() const {return m_name;}
       inline void setName(const std::string& name) {m_name=name;}
friend class boost::serialization::access;
       template <class Archive> void serialize(Archive& ar, const 
unsigned int version){
           ar & m_name;
       }
   protected:
       std::string m_name;
};
Sensor::Sensor(const std::string& name){
   m_name=name;
}
Sensor::~Sensor(){
}
class SensorReading{
   public:
       SensorReading(const Sensor* s=0, double time=0);
       virtual ~SensorReading();
       inline double getTime() const {return m_time;}
       inline void setTime(double t) {m_time=t;}
       inline const Sensor* getSensor() const {return m_sensor;}
       inline void print(){
           cout << "(" << m_time << "," << m_sensor->getName() << ")" << 
endl;
       }
       friend class boost::serialization::access;
       template <class Archive> void serialize(Archive& ar, const 
unsigned int version){
           ar & m_time & m_sensor;
       }
protected:
       double m_time;
       const Sensor* m_sensor;
};
SensorReading::SensorReading(const Sensor* s, double t){
   m_sensor=s;
   m_time=t;
}
SensorReading::~SensorReading(){}
template <class A> void saveIntoFileSens(SensorReading& sr, const char* 
file){
       ofstream ofile(file);
       A ar(ofile);
       ar << sr;
       ofile.close();
}
template <class A> void loadFromFileSens(SensorReading& sr, const char* 
file){
   ifstream ifile(file);
   A ar(ifile);
   ar >> sr;
   ifile.close();
}
/*
* MAIN
*
*/
int main(){
Sensor s = Sensor("SensorNom");
   SensorReading senr = SensorReading(&s,67);
saveIntoFileSens<text_oarchive>(senr, "out.txt");
   loadFromFileSens<text_iarchive>(senr, "out.txt");
return 0;
}
----- Original Message ----- 
From: "Simon Ruffieux" <simon.ruffieux@gmail.com>
Newsgroups: gmane.comp.lib.boost.user
To: <boost-users@lists.boost.org>
Sent: Friday, January 15, 2010 9:04 AM
Subject: Re: Serialization of pointers ? --> loadingnotworking...
...
Thanks for your quick answer !
But the orientedPoints do work do work perfectly ! (Even without 
specifying the derived class)
The problem is with the pointer to Sensor* contained in the 
SensorReading class .... And it seems to me this is not a derived class 
....
I'll keep trying ...
----- Original Message ----- 
From: "Robert Ramey" <ramey@rrsd.com>
Newsgroups: gmane.comp.lib.boost.user
To: <boost-users@lists.boost.org>
Sent: Thursday, January 14, 2010 5:56 PM
Subject: Re: Serialization of pointers ? --> loading notworking...
...
replace
   friend class boost::serialization::access;
   template <class Archive> void serialize(Archive& ar, const unsigned 
int version){
       ar & this->x & this->y & theta;
   }
with something like:
   friend class boost::serialization::access;
   template <class Archive> void serialize(Archive& ar, const unsigned 
int version){
       ar & boost::serialization::base_object<?>(*this);
   }
Look through the documentation and samples on how to serialize derived 
classes.
Robert Ramey