Question

I have a small hierarchy of objects that I need to serialize and transmit via a socket connection. I need to both serialize the object, then deserialize it based on what type it is. Is there an easy way to do this in C++ (as there is in Java)?

Just to be clear, I’m looking for methods on converting an object into an array of bytes, then back into an object. I can handle the socket transmission.

Answer 1

Talking about serialization, the boost serialization API comes to my mind. As for transmitting the serialized data over the net, I’d either use Berkeley sockets or the asio library.

If you want to serialize your objects to a byte array, you can use the boost serializer in the following way (taken from the tutorial site):

#include <boost/archive/binary_oarchive.hpp> #include <boost/archive/binary_iarchive.hpp> class gps_position { private:     friend class boost::serialization::access;     template<class Archive>     void serialize(Archive & ar, const unsigned int version)     {         ar & degrees;         ar & minutes;         ar & seconds;     }     int degrees;     int minutes;     float seconds;  public:     gps_position(){};     gps_position(int d, int m, float s) :     degrees(d), minutes(m), seconds(s)     {} }; 

Actual serialization is then pretty easy:

#include <fstream> std::ofstream ofs("filename.dat", std::ios::binary);      // create class instance     const gps_position g(35, 59, 24.567f);      // save data to archive     {         boost::archive::binary_oarchive oa(ofs);         // write class instance to archive         oa << g;         // archive and stream closed when destructors are called     } 

Deserialization works in an analogous manner.

There are also mechanisms which let you handle serialization of pointers (complex data structures like tress etc are no problem), derived classes and you can choose between binary and text serialization. Besides all STL containers are supported out of the box.