| 1 | /*
|
|---|
| 2 | * Project: MoleCuilder
|
|---|
| 3 | * Description: creates and alters molecular systems
|
|---|
| 4 | * Copyright (C) 2010 University of Bonn. All rights reserved.
|
|---|
| 5 | * Please see the LICENSE file or "Copyright notice" in builder.cpp for details.
|
|---|
| 6 | */
|
|---|
| 7 |
|
|---|
| 8 | /**
|
|---|
| 9 | * \file serialization.dox
|
|---|
| 10 | *
|
|---|
| 11 | * Here, we explain what serialization is and how it is used within MoleCuilder.
|
|---|
| 12 | *
|
|---|
| 13 | * Created on: Oct 11, 2011
|
|---|
| 14 | * Author: heber
|
|---|
| 15 | */
|
|---|
| 16 |
|
|---|
| 17 | /** \page serialization Serialization
|
|---|
| 18 | *
|
|---|
| 19 | * Serialization is a mighty concept. The is only possible within an object-
|
|---|
| 20 | * oriented framework. The member variables of a class make up its internal
|
|---|
| 21 | * state. By storing this state, creating another instance and restoring
|
|---|
| 22 | * the variables to this state, we may in essence clone the instance. However,
|
|---|
| 23 | * we obtain additional control as to the moment of restoration because the
|
|---|
| 24 | * internal state is stored temporarily. To allow for this storage all of
|
|---|
| 25 | * these variables have to be \e serialized.
|
|---|
| 26 | *
|
|---|
| 27 | * Serialization refers to putting one after another into a writable form
|
|---|
| 28 | * (e.g. convert to string and write into a stringstream) and eventually
|
|---|
| 29 | * in reverse order to read them one by one from this writable form and
|
|---|
| 30 | * cast them back into their original type.
|
|---|
| 31 | *
|
|---|
| 32 | * Here, this is done via boost::serialization.
|
|---|
| 33 | *
|
|---|
| 34 | * \attention The serialization headers do not mingle well with \b MemDebug.hpp.
|
|---|
| 35 | * Hence, place them before MemDebug.hpp as they do funny stuff with the
|
|---|
| 36 | * new() operator.
|
|---|
| 37 | *
|
|---|
| 38 | * Serialization is so powerful because the stored state can be stored to
|
|---|
| 39 | * disk, transfered to another thread or even to another computer. If received
|
|---|
| 40 | * by a compatible code, the instance is recreated and computation can be
|
|---|
| 41 | * continued elsewhere.
|
|---|
| 42 | *
|
|---|
| 43 | * For the moment we use it for creating an undo state within the Action's.
|
|---|
| 44 | * I.e. we store the state of all instances that are modified by an Action's
|
|---|
| 45 | * doings and may in Action::performUndo() just re-create the unmodified
|
|---|
| 46 | * instance by loading them from the serializing archive.
|
|---|
| 47 | *
|
|---|
| 48 | * \section serialization-add How to make your class serializable.
|
|---|
| 49 | *
|
|---|
| 50 | * \subsection serialization-add-simple The simple case
|
|---|
| 51 | *
|
|---|
| 52 | * All you need to do with your newly created class foo is this:
|
|---|
| 53 | * \code
|
|---|
| 54 | * class foo {
|
|---|
| 55 | * ...
|
|---|
| 56 | * private:
|
|---|
| 57 | * friend class boost::serialization::access;
|
|---|
| 58 | * template<class Archive>
|
|---|
| 59 | * void serialize(Archive & ar, const unsigned int version) const
|
|---|
| 60 | * {
|
|---|
| 61 | * ar & content;
|
|---|
| 62 | * }
|
|---|
| 63 | * ...
|
|---|
| 64 | * double content;
|
|---|
| 65 | * };
|
|---|
| 66 | * \endcode
|
|---|
| 67 | * This will implement a serialization function for both directions for the
|
|---|
| 68 | * member variable content. I.e. we may now store a class instance as this:
|
|---|
| 69 | * \code
|
|---|
| 70 | * #include <boost/archive/text_oarchive.hpp>
|
|---|
| 71 | * std::stringstream stream;
|
|---|
| 72 | * boost::archive::text_oarchive oa(stream);
|
|---|
| 73 | * oa << diagonal;
|
|---|
| 74 | * \endcode
|
|---|
| 75 | * This will store the state of the class in the stringstream \a stream.
|
|---|
| 76 | * Getting the instance back is then as easy as
|
|---|
| 77 | * \code
|
|---|
| 78 | * #include <boost/archive/text_iarchive.hpp>
|
|---|
| 79 | * boost::archive::text_iarchive ia(stream);
|
|---|
| 80 | * RealSpaceMatrix *newm;
|
|---|
| 81 | * ia >> newm;
|
|---|
| 82 | * \endcode
|
|---|
| 83 | *
|
|---|
| 84 | * \subsection serialization-add-complicated The more complicated case
|
|---|
| 85 | *
|
|---|
| 86 | * It gets trickier when load and store need to be done differently, e.h.
|
|---|
| 87 | * \code
|
|---|
| 88 | * class foo {
|
|---|
| 89 | * ...
|
|---|
| 90 | * private:
|
|---|
| 91 | * friend class boost::serialization::access;
|
|---|
| 92 | * // serialization
|
|---|
| 93 | * template<class Archive>
|
|---|
| 94 | * void save(Archive & ar, const unsigned int version) const
|
|---|
| 95 | * {
|
|---|
| 96 | * ar & content;
|
|---|
| 97 | * }
|
|---|
| 98 | * template<class Archive>
|
|---|
| 99 | * void load(Archive & ar, const unsigned int version)
|
|---|
| 100 | * {
|
|---|
| 101 | * ar & content;
|
|---|
| 102 | * createViews();
|
|---|
| 103 | * }
|
|---|
| 104 | * BOOST_SERIALIZATION_SPLIT_MEMBER()
|
|---|
| 105 | * ...
|
|---|
| 106 | * }
|
|---|
| 107 | * \endcode
|
|---|
| 108 | * Here, we split serialize() function into distinct load() and save() because
|
|---|
| 109 | * we have to call an additional function to fully re-store the instance, i.e.
|
|---|
| 110 | * it creates some internal reference arrays (Views) in a specific manner.
|
|---|
| 111 | *
|
|---|
| 112 | * The serialize functions can also be added externally, i.e. outside of the
|
|---|
| 113 | * scope of the class, but can then access only public members (except we
|
|---|
| 114 | * again make it a friend).
|
|---|
| 115 | *
|
|---|
| 116 | *
|
|---|
| 117 | * \date 2011-10-31
|
|---|
| 118 | */
|
|---|
