FACT++  1.0
Public Member Functions | Private Attributes | List of all members
EventImp Class Reference

A general base-class describing events issues in a state machine. More...

#include <EventImp.h>

+ Inheritance diagram for EventImp:
+ Collaboration diagram for EventImp:

Public Member Functions

 EventImp ()
 Constructor. Stores the target state given. More...
 
 EventImp (const EventImp &cmd)
 Copy constructor. More...
 
virtual ~EventImp ()
 
virtual void SetDescription (const std::string &)
 
virtual std::string GetDescription () const
 
EventImp & AssignFunction (const std::function< int(const EventImp &)> &func=std::function< int(const EventImp &)>())
 
bool HasFunc () const
 
int ExecFunc () const
 
EventImp & operator() (const std::function< int(const EventImp &)> &func)
 
EventImp & operator() (const std::string str)
 
EventImp & operator() (const char *str)
 
EventImp & operator() (int state)
 
virtual void Print (std::ostream &out, bool strip=false) const
 
virtual void Print (bool strip=false) const
 
void AddAllowedState (int state)
 
void AddAllowedStates (const std::string &states)
 
bool IsStateAllowed (int state) const
 
virtual std::string GetName () const
 
virtual std::string GetFormat () const
 
virtual const void * GetData () const
 
virtual size_t GetSize () const
 
virtual Time GetTime () const
 
virtual int GetQoS () const
 
virtual bool IsEmpty () const
 
std::string GetTimeAsStr (const char *fmt) const
 
uint64_t GetJavaDate () const
 
template<typename T >
T Get (size_t offset=0) const
 
template<typename T >
const T * Ptr (size_t offset=0) const
 
template<typename T >
const T & Ref (size_t offset=0) const
 
const char * GetText () const
 
bool GetBool () const
 
int16_t GetShort () const
 
uint16_t GetUShort () const
 
int32_t GetInt () const
 
uint32_t GetUInt () const
 
int64_t GetXtra () const
 
uint64_t GetUXtra () const
 
float GetFloat () const
 
double GetDouble () const
 
std::vector< char > GetVector () const
 
std::string GetString () const
 

Private Attributes

std::vector< int > fAllowedStates
 
std::function< int(const EventImp &)> fFunction
 List of states in which this event is allowed. More...
 

Detailed Description

A general base-class describing events issues in a state machine.

purpose

The general purpose of this class is to describe an event which can occur in one of our StateMachines. It provides pointers to data associated with the event, a target state and stores the states in which issuing this event is allowed. The target state might be negative to describe that no transition of the state is requested.

Such an event canjust be a description of an event, but can also be an issued event which already contain data.

The format can, but need not, contain the format of the data area. As a rule, it should follow the format also used in the DIM network.

functions to an event

To any event a function call can be assigned. Thanks to boost::bind there are various and different very powerful ways to do that.

The function assigned with AssignFunction must return int. When it is executed it is given a const reference of the current event as an argument, i.e. if you want to get such a reference in your function, you can reference it using the placeholder _1. (Remark: it is allowe to omit the _1 placeholder if no reference to the EventImp object is needed)

A few examples:

int function(const EventImp &evt, int i, const char *txt) { return i; }
EventImp evt;
evt.AssignFunction(boost::bind(function, _1, 7, "hallo"));
cout << evt.Exec() << endl;
// 7

When the function is executed later via ExecFunc() in will get a reference to the executing EventImp as its first argument (indicated by '_1'), it will get 7 and "hallo" as second and third argument.

int function(int i, const char *txt, const EventImp &evt) { return i; }
EventImp evt;
evt.AssignFunction(boost::bind(function, 7, "hallo", _1));
cout << evt.Exec() << endl;
// 7

Is the same example than the one above, but the arguments are in a different order.

class A
{
int function(const EventImp &evt, int i, const char *txt)
{
cout << this << endl; return i;
}
};
A a;
EventImp evt;
evt.AssignFunction(boost::bind(&A::function, &a, _1, 7, "hallo"));
cout << evt.Exec() << endl;
// &a
// 7

The advanatge of boost::bind is that it also works for member functions of classes. In this case the first argument after the function-pointer must be a pointer to a valid class-object. This can also be this if called from within a class object.

Also note that everything (as usual) which is not a reference is copied when the bind function is invoked. If you want to distribute a reference instead use ref(something), like

int function(int &i) { return i; }
int j = 5;
EventImp evt;
evt.AssignFunction(bind(function, ref(j));
j = 7;
cout << evt.Exec() << endl;
// 7

Note, that you are responsible for the validity, that means: Do not destroy your object (eg. reference to j) while bind might still be called later, or a pointer to this.

References

Todo:
Add link to DIM format
Examples:
chatserv.cc.

Definition at line 11 of file EventImp.h.

The documentation for this class was generated from the following files: