///\ingroup graphbits

 //\ingroup graphbits

 ///\file

 //\file

 ///\brief Observer notifier for graph alteration observers.

 //\brief Observer notifier for graph alteration observers.

   /// \ingroup graphbits

   // \ingroup graphbits

   ///

   //

   /// \brief Notifier class to notify observes about alterations in

   // \brief Notifier class to notify observes about alterations in

   /// a container.

   // a container.

   ///

   //

   /// The simple graph's can be refered as two containers, one node container

   // The simple graph's can be refered as two containers, one node container

   /// and one edge container. But they are not standard containers they

   // and one edge container. But they are not standard containers they

   /// does not store values directly they are just key continars for more

   // does not store values directly they are just key continars for more

   /// value containers which are the node and edge maps.

   // value containers which are the node and edge maps.

   ///

   //

   /// The graph's node and edge sets can be changed as we add or erase

   // The graph's node and edge sets can be changed as we add or erase

   /// nodes and edges in the graph. LEMON would like to handle easily

   // nodes and edges in the graph. LEMON would like to handle easily

   /// that the node and edge maps should contain values for all nodes or

   // that the node and edge maps should contain values for all nodes or

   /// edges. If we want to check on every indicing if the map contains

   // edges. If we want to check on every indicing if the map contains

   /// the current indicing key that cause a drawback in the performance

   // the current indicing key that cause a drawback in the performance

   /// in the library. We use another solution we notify all maps about

   // in the library. We use another solution we notify all maps about

   /// an alteration in the graph, which cause only drawback on the

   // an alteration in the graph, which cause only drawback on the

   /// alteration of the graph.

   // alteration of the graph.

   ///

   //

   /// This class provides an interface to the container. The \e first() and \e

   // This class provides an interface to the container. The \e first() and \e

   /// next() member functions make possible to iterate on the keys of the

   // next() member functions make possible to iterate on the keys of the

   /// container. The \e id() function returns an integer id for each key.

   // container. The \e id() function returns an integer id for each key.

   /// The \e maxId() function gives back an upper bound of the ids.

   // The \e maxId() function gives back an upper bound of the ids.

   ///

   //

   /// For the proper functonality of this class, we should notify it

   // For the proper functonality of this class, we should notify it

   /// about each alteration in the container. The alterations have four type

   // about each alteration in the container. The alterations have four type

   /// as \e add(), \e erase(), \e build() and \e clear(). The \e add() and

   // as \e add(), \e erase(), \e build() and \e clear(). The \e add() and

   /// \e erase() signals that only one or few items added or erased to or

   // \e erase() signals that only one or few items added or erased to or

   /// from the graph. If all items are erased from the graph or from an empty

   // from the graph. If all items are erased from the graph or from an empty

   /// graph a new graph is builded then it can be signaled with the

   // graph a new graph is builded then it can be signaled with the

   /// clear() and build() members. Important rule that if we erase items

   // clear() and build() members. Important rule that if we erase items

   /// from graph we should first signal the alteration and after that erase

   // from graph we should first signal the alteration and after that erase

   /// them from the container, on the other way on item addition we should

   // them from the container, on the other way on item addition we should

   /// first extend the container and just after that signal the alteration.

   // first extend the container and just after that signal the alteration.

   ///

   //

   /// The alteration can be observed with a class inherited from the

   // The alteration can be observed with a class inherited from the

   /// \e ObserverBase nested class. The signals can be handled with

   // \e ObserverBase nested class. The signals can be handled with

   /// overriding the virtual functions defined in the base class.  The

   // overriding the virtual functions defined in the base class.  The

   /// observer base can be attached to the notifier with the

   // observer base can be attached to the notifier with the

   /// \e attach() member and can be detached with detach() function. The

   // \e attach() member and can be detached with detach() function. The

   /// alteration handlers should not call any function which signals

   // alteration handlers should not call any function which signals

   /// an other alteration in the same notifier and should not

   // an other alteration in the same notifier and should not

   /// detach any observer from the notifier.

   // detach any observer from the notifier.

   ///

   //

   /// Alteration observers try to be exception safe. If an \e add() or

   // Alteration observers try to be exception safe. If an \e add() or

   /// a \e clear() function throws an exception then the remaining

   // a \e clear() function throws an exception then the remaining

   /// observeres will not be notified and the fulfilled additions will

   // observeres will not be notified and the fulfilled additions will

   /// be rolled back by calling the \e erase() or \e clear()

   // be rolled back by calling the \e erase() or \e clear()

   /// functions. Thence the \e erase() and \e clear() should not throw

   // functions. Thence the \e erase() and \e clear() should not throw

   /// exception. Actullay, it can be throw only \ref ImmediateDetach 

   // exception. Actullay, it can be throw only \ref ImmediateDetach

   /// exception which detach the observer from the notifier.

   // exception which detach the observer from the notifier.

   ///

   //

   /// There are some place when the alteration observing is not completly

   // There are some place when the alteration observing is not completly

   /// reliable. If we want to carry out the node degree in the graph

   // reliable. If we want to carry out the node degree in the graph

   /// as in the \ref InDegMap and we use the reverseEdge that cause

   // as in the \ref InDegMap and we use the reverseEdge that cause

   /// unreliable functionality. Because the alteration observing signals

   // unreliable functionality. Because the alteration observing signals

   /// only erasing and adding but not the reversing it will stores bad

   // only erasing and adding but not the reversing it will stores bad

   /// degrees. The sub graph adaptors cannot signal the alterations because

   // degrees. The sub graph adaptors cannot signal the alterations because

   /// just a setting in the filter map can modify the graph and this cannot

   // just a setting in the filter map can modify the graph and this cannot

   /// be watched in any way.

   // be watched in any way.

   ///

   //

   /// \param _Container The container which is observed.

   // \param _Container The container which is observed.

   /// \param _Item The item type which is obserbved.

   // \param _Item The item type which is obserbved.

     /// \brief Exception which can be called from \e clear() and

     // \brief Exception which can be called from \e clear() and

     /// \e erase().

     // \e erase().

     ///

     //

     /// From the \e clear() and \e erase() function only this

     // From the \e clear() and \e erase() function only this

     /// exception is allowed to throw. The exception immediatly

     // exception is allowed to throw. The exception immediatly

     /// detaches the current observer from the notifier. Because the

     // detaches the current observer from the notifier. Because the

     /// \e clear() and \e erase() should not throw other exceptions

     // \e clear() and \e erase() should not throw other exceptions

     /// it can be used to invalidate the observer.

     // it can be used to invalidate the observer.

     /// \brief ObserverBase is the base class for the observers.

     // \brief ObserverBase is the base class for the observers.

     ///

     //

     /// ObserverBase is the abstract base class for the observers.

     // ObserverBase is the abstract base class for the observers.

     /// It will be notified about an item was inserted into or

     // It will be notified about an item was inserted into or

     /// erased from the graph.

     // erased from the graph.

     ///

     //

     /// The observer interface contains some pure virtual functions

     // The observer interface contains some pure virtual functions

     /// to override. The add() and erase() functions are

     // to override. The add() and erase() functions are

     /// to notify the oberver when one item is added or

     // to notify the oberver when one item is added or

     /// erased.

     // erased.

     ///

     //

     /// The build() and clear() members are to notify the observer

     // The build() and clear() members are to notify the observer

     /// about the container is built from an empty container or

     // about the container is built from an empty container or

     /// is cleared to an empty container.

     // is cleared to an empty container.

       /// \brief Default constructor.

       // \brief Default constructor.

       ///

       //

       /// Default constructor for ObserverBase.

       // Default constructor for ObserverBase.

       ///

       /// \brief Constructor which attach the observer into notifier.

       // \brief Constructor which attach the observer into notifier.

       ///

       //

       /// Constructor which attach the observer into notifier.

       // Constructor which attach the observer into notifier.

       /// \brief Constructor which attach the obserever to the same notifier.

       // \brief Constructor which attach the obserever to the same notifier.

       ///

       //

       /// Constructor which attach the obserever to the same notifier as

       // Constructor which attach the obserever to the same notifier as

       /// the other observer is attached to.

       // the other observer is attached to.

       /// \brief Destructor

       // \brief Destructor

       /// \brief Attaches the observer into an AlterationNotifier.

       // \brief Attaches the observer into an AlterationNotifier.

       ///

       //

       /// This member attaches the observer into an AlterationNotifier.

       // This member attaches the observer into an AlterationNotifier.

       ///

       /// \brief Detaches the observer into an AlterationNotifier.

       // \brief Detaches the observer into an AlterationNotifier.

       ///

       //

       /// This member detaches the observer from an AlterationNotifier.

       // This member detaches the observer from an AlterationNotifier.

       ///

       /// \brief Gives back a pointer to the notifier which the map

       // \brief Gives back a pointer to the notifier which the map

       /// attached into.

       // attached into.

       ///

       //

       /// This function gives back a pointer to the notifier which the map

       // This function gives back a pointer to the notifier which the map

       /// attached into.

       // attached into.

       ///

       /// Gives back true when the observer is attached into a notifier.

       // Gives back true when the observer is attached into a notifier.

       /// \brief The member function to notificate the observer about an

       // \brief The member function to notificate the observer about an

       /// item is added to the container.

       // item is added to the container.

       ///

       //

       /// The add() member function notificates the observer about an item

       // The add() member function notificates the observer about an item

       /// is added to the container. It have to be overrided in the

       // is added to the container. It have to be overrided in the

       /// subclasses.

       // subclasses.

       /// \brief The member function to notificate the observer about

       // \brief The member function to notificate the observer about

       /// more item is added to the container.

       // more item is added to the container.

       ///

       //

       /// The add() member function notificates the observer about more item

       // The add() member function notificates the observer about more item

       /// is added to the container. It have to be overrided in the

       // is added to the container. It have to be overrided in the

       /// subclasses.

       // subclasses.

       /// \brief The member function to notificate the observer about an

       // \brief The member function to notificate the observer about an

       /// item is erased from the container.

       // item is erased from the container.

       ///

       //

       /// The erase() member function notificates the observer about an

       // The erase() member function notificates the observer about an

       /// item is erased from the container. It have to be overrided in

       // item is erased from the container. It have to be overrided in

       /// the subclasses.

       // the subclasses.

       /// \brief The member function to notificate the observer about

       // \brief The member function to notificate the observer about

       /// more item is erased from the container.

       // more item is erased from the container.

       ///

       //

       /// The erase() member function notificates the observer about more item

       // The erase() member function notificates the observer about more item

       /// is erased from the container. It have to be overrided in the

       // is erased from the container. It have to be overrided in the

       /// subclasses.

       // subclasses.

       /// \brief The member function to notificate the observer about the

       // \brief The member function to notificate the observer about the

       /// container is built.

       // container is built.

       ///

       //

       /// The build() member function notificates the observer about the

       // The build() member function notificates the observer about the

       /// container is built from an empty container. It have to be

       // container is built from an empty container. It have to be

       /// overrided in the subclasses.

       // overrided in the subclasses.

       /// \brief The member function to notificate the observer about all

       // \brief The member function to notificate the observer about all

       /// items are erased from the container.

       // items are erased from the container.

       ///

       //

       /// The clear() member function notificates the observer about all

       // The clear() member function notificates the observer about all

       /// items are erased from the container. It have to be overrided in

       // items are erased from the container. It have to be overrided in

       /// the subclasses.

       // the subclasses.

     /// \brief Default constructor.

     // \brief Default constructor.

     ///

     //

     /// The default constructor of the AlterationNotifier.

     // The default constructor of the AlterationNotifier.

     /// It creates an empty notifier.

     // It creates an empty notifier.

     /// \brief Constructor.

     // \brief Constructor.

     ///

     //

     /// Constructor with the observed container parameter.

     // Constructor with the observed container parameter.

     /// \brief Copy Constructor of the AlterationNotifier.

     // \brief Copy Constructor of the AlterationNotifier.

     ///

     //

     /// Copy constructor of the AlterationNotifier.

     // Copy constructor of the AlterationNotifier.

     /// It creates only an empty notifier because the copiable

     // It creates only an empty notifier because the copiable

     /// notifier's observers have to be registered still into that notifier.

     // notifier's observers have to be registered still into that notifier.

     /// \brief Destructor.

     // \brief Destructor.

     ///

     //

     /// Destructor of the AlterationNotifier.

     // Destructor of the AlterationNotifier.

     ///

     /// \brief Sets the container.

     // \brief Sets the container.

     ///

     //

     /// Sets the container.

     // Sets the container.

     // \brief First item in the container.

     //

     /// \brief First item in the container.

     // Returns the first item in the container. It is

     ///

     // for start the iteration on the container.

     /// Returns the first item in the container. It is

     /// for start the iteration on the container.

     /// \brief Next item in the container.

     // \brief Next item in the container.

     ///

     //

     /// Returns the next item in the container. It is

     // Returns the next item in the container. It is

     /// for iterate on the container.

     // for iterate on the container.

     /// \brief Returns the id of the item.

     // \brief Returns the id of the item.

     ///

     //

     /// Returns the id of the item provided by the container.

     // Returns the id of the item provided by the container.

     /// \brief Returns the maximum id of the container.

     // \brief Returns the maximum id of the container.

     ///

     //

     /// Returns the maximum id of the container.

     // Returns the maximum id of the container.

     /// \brief Notifies all the registed observers about an item added to

     // \brief Notifies all the registed observers about an item added to

     /// the container.

     // the container.

     ///

     //

     /// It notifies all the registed observers about an item added to

     // It notifies all the registed observers about an item added to

     /// the container.

     // the container.

     ///

     /// \brief Notifies all the registed observers about more item added to

     // \brief Notifies all the registed observers about more item added to

     /// the container.

     // the container.

     ///

     //

     /// It notifies all the registed observers about more item added to

     // It notifies all the registed observers about more item added to

     /// the container.

     // the container.

     ///

     /// \brief Notifies all the registed observers about an item erased from

     // \brief Notifies all the registed observers about an item erased from

     /// the container.

     // the container.

     ///

     //

     /// It notifies all the registed observers about an item erased from

     // It notifies all the registed observers about an item erased from

     /// the container.

     // the container.

     ///

     /// \brief Notifies all the registed observers about more item erased

     // \brief Notifies all the registed observers about more item erased

     /// from the container.

     // from the container.

     ///

     //

     /// It notifies all the registed observers about more item erased from

     // It notifies all the registed observers about more item erased from

     /// the container.

     // the container.

     ///

     /// \brief Notifies all the registed observers about the container is

     // \brief Notifies all the registed observers about the container is

     /// built.

     // built.

     ///

     //

     /// Notifies all the registed observers about the container is built

     // Notifies all the registed observers about the container is built

     /// from an empty container.

     // from an empty container.

     /// \brief Notifies all the registed observers about all items are

     // \brief Notifies all the registed observers about all items are

     /// erased.

     // erased.

     ///

     //

     /// Notifies all the registed observers about all items are erased

     // Notifies all the registed observers about all items are erased

     /// from the container.

     // from the container.