Utils::ObjectDispatcher< DispatchBase, Sender > Class Template Reference

#include <ObjectDispatcher.h> [code]

Inheritance diagram for Utils::ObjectDispatcher< DispatchBase, Sender >:

[legend]List of all members.

Detailed Description

template<typename DispatchBase, typename Sender = void>
class Utils::ObjectDispatcher< DispatchBase, Sender >

Provides object dispatching based on typeid().

This is a helper class that provides typeid() based object dispatching.

Object dispatching is an alternative to the double-dispatching technique used in the Visitor Pattern. ObjectDispatcher is extremely helpful if you want to avoid switching on type codes just in order to cast and forward an object to the appropriate handler.

Template parameters:

DispatchBase is the base class of the polymorphic class hierarchy objects from which you will be dispatching.
Sender is the type of the object invoking the dispatch() method. This type parameter could be void (the default) which essentially disallows you to register handlers that also receive a pointer to the Sender.

ObjectDispatcher supports three types of handlers:

catch-all handlers - invoked for each dispatched object, added using registerCatchAllHandler()
type handlers - invoked only if the runtime type of the dispatched object matches the object type of the handler, added using registerTypeHandler()
not-handled handlers - invoked for each dispatched object for which no type handlers were registered, added using registerNotHandledHandler()

A handler could be a non-member function, static class function, or a class member function.

The first parameter of catch-all and not-handled handler functions must be of type const DispatchBase &. The first parameter of type handler function must be const DispatchBaseDerived &.

Each of the handlers might have a second parameter of type Sender *. This second parameter would contain the address of the object that invoked the dispatch() method. This value could also be 0 if the sender chose not to give its address.

Once you call the dispatch() method, it will invoke all handlers corresponding registered handlers (see dispatch() for more details).

Todo:: Any idea how to reduce the code duplication in all Handler derived classes? That would possibly also make it possible to get rid of the four register-handler overloads per handler type.

Definition at line 77 of file ObjectDispatcher.h.

Public Types

typedef Callable< void(const
DispatchBase &)> DispatchBaseHandler

typedef Callable< void(const
DispatchBase &, Sender *) DispatchBaseSenderHandler )

Public Member Functions

ObjectDispatcher ()

Default constructor.

~ObjectDispatcher ()

Destructor. Frees all allocated memory.

void registerCatchAllHandler (const DispatchBaseHandler &handler)

Register a non-member/static-member function as a catch-all handler.

void registerCatchAllHandler (const DispatchBaseSenderHandler &handler)

Register a member function as a catch-all handler.

template<typename T>

void registerTypeHandler (const Callable< void(const T &)> &handler)

Register a non-member/static-member function as type handler.

template<typename T>

void registerTypeHandler (const Callable< void(const T &, Sender *)> &handler)

Register a member function as type handler.

template<typename T>

void unregisterTypeHandler (const Callable< void(const T &)> &handler)

Unregister a non-member/static-member function as type handler.

template<typename T>

void unregisterTypeHandler (const Callable< void(const T &, Sender *)> &handler)

Unregister a member function as type handler.

void registerNotHandledHandler (const DispatchBaseHandler &handler)

Register a non-member/static-member function as type handler.

void registerNotHandledHandler (const DispatchBaseSenderHandler &handler)

Register a member function as type handler.

bool dispatch (const DispatchBase &object, Sender *sender=0)

Dispatch object to the corresponding registered handlers.

Private Member Functions

void doRegisterCatchAllHandler (Handler *handler)

Helper to register handler as a type handler for T.

template<typename T>

void doRegisterHandler (Handler *handler)

Helper to register handler as a type handler for T.

template<typename T>

void doUnregisterHandler (Handler *handler)

Helper to register handler as a type handler for T.

void doRegisterNotHandledHandler (Handler *handler)

Helper to register handler as a type handler for T.

void dispatchToCatchAllHandlers (const DispatchBase &object, Sender *sender)

Helper to dispatch to all the catch-all registered handlers.

bool dispatchToTypeHandlers (const DispatchBase &object, Sender *sender)

Helper to dispatch to all type handlers matching typeid (object).

void dispatchToNotHandledHandlers (const DispatchBase &object, Sender *sender)

Helper to dispatch to all not-handled handlers.

Private Attributes

QList< Handler * > catchAllHandlers

QMultiMap< const std::type_info *,
Handler * > handlers

QList< Handler * > notHandledHandlers

Classes

struct Handler

Interface to a Handler wrapper. More...

class TypeHandler

class TypeHandlerWithSender

Member Typedef Documentation

template<typename DispatchBase, typename Sender = void>

typedef Callable<void (const DispatchBase &)> Utils::ObjectDispatcher< DispatchBase, Sender >::DispatchBaseHandler

Definition at line 80 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

typedef Callable<void (const DispatchBase &, Sender *) Utils::ObjectDispatcher< DispatchBase, Sender >::DispatchBaseSenderHandler)

Definition at line 82 of file ObjectDispatcher.h.

Constructor & Destructor Documentation

template<typename DispatchBase, typename Sender = void>

Utils::ObjectDispatcher< DispatchBase, Sender >::ObjectDispatcher ( ) [inline]

Default constructor.

Definition at line 85 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

Utils::ObjectDispatcher< DispatchBase, Sender >::~ObjectDispatcher ( ) [inline]

Destructor. Frees all allocated memory.

Definition at line 91 of file ObjectDispatcher.h.

Member Function Documentation

template<typename DispatchBase, typename Sender = void>

bool Utils::ObjectDispatcher< DispatchBase, Sender >::dispatch ( const DispatchBase & object,

Sender * sender = 0

) [inline]

Dispatch object to the corresponding registered handlers.

Parameters:

object is the object to dispatch.

sender is the object to pass to the handler as sender.

Returns:
true if at least one type-handler was invoked, no matter how many catch-all and not-handled handlers were invoked too.
false if no type-handler was invoked, no matter whether any catch-all or not-handled handlers were invoked.
All catch-all handlers will be invoked. Any type-handlers matching the runtime type of object will be inkoved. If no type handler is found for the runtime type of object, then all registered not-handled handlers will be invoked.
Definition at line 177 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::dispatchToCatchAllHandlers ( const DispatchBase & object,

Sender * sender

) [inline, private]

Helper to dispatch to all the catch-all registered handlers.

Definition at line 226 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::dispatchToNotHandledHandlers ( const DispatchBase & object,

Sender * sender

) [inline, private]

Helper to dispatch to all not-handled handlers.

Definition at line 253 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

bool Utils::ObjectDispatcher< DispatchBase, Sender >::dispatchToTypeHandlers ( const DispatchBase & object,

Sender * sender

) [inline, private]

Helper to dispatch to all type handlers matching typeid (object).
Gets the list of all handlers already registered for the runtime type of object and iterates in reverse order because the most recently inserted handlers are first in the list. We want the order in which the handlers are called to be the order in which the handlers are registered.
Definition at line 240 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::doRegisterCatchAllHandler ( Handler * handler ) [inline, private]

Helper to register handler as a type handler for T.

Definition at line 190 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

template<typename T>

void Utils::ObjectDispatcher< DispatchBase, Sender >::doRegisterHandler ( Handler * handler ) [inline, private]

Helper to register handler as a type handler for T.

Definition at line 197 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::doRegisterNotHandledHandler ( Handler * handler ) [inline, private]

Helper to register handler as a type handler for T.

Definition at line 220 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

template<typename T>

void Utils::ObjectDispatcher< DispatchBase, Sender >::doUnregisterHandler ( Handler * handler ) [inline, private]

Helper to register handler as a type handler for T.

Definition at line 205 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::registerCatchAllHandler ( const DispatchBaseSenderHandler & handler ) [inline]

Register a member function as a catch-all handler.

Definition at line 110 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::registerCatchAllHandler ( const DispatchBaseHandler & handler ) [inline]

Register a non-member/static-member function as a catch-all handler.

Definition at line 103 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::registerNotHandledHandler ( const DispatchBaseSenderHandler & handler ) [inline]

Register a member function as type handler.

Definition at line 156 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

void Utils::ObjectDispatcher< DispatchBase, Sender >::registerNotHandledHandler ( const DispatchBaseHandler & handler ) [inline]

Register a non-member/static-member function as type handler.

Definition at line 149 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

template<typename T>

void Utils::ObjectDispatcher< DispatchBase, Sender >::registerTypeHandler ( const Callable< void(const T &, Sender *)> & handler ) [inline]

Register a member function as type handler.

Definition at line 126 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

template<typename T>

void Utils::ObjectDispatcher< DispatchBase, Sender >::registerTypeHandler ( const Callable< void(const T &)> & handler ) [inline]

Register a non-member/static-member function as type handler.

Definition at line 118 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

template<typename T>

void Utils::ObjectDispatcher< DispatchBase, Sender >::unregisterTypeHandler ( const Callable< void(const T &, Sender *)> & handler ) [inline]

Unregister a member function as type handler.

Definition at line 142 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

template<typename T>

void Utils::ObjectDispatcher< DispatchBase, Sender >::unregisterTypeHandler ( const Callable< void(const T &)> & handler ) [inline]

Unregister a non-member/static-member function as type handler.

Definition at line 134 of file ObjectDispatcher.h.

Member Data Documentation

template<typename DispatchBase, typename Sender = void>

QList<Handler *> Utils::ObjectDispatcher< DispatchBase, Sender >::catchAllHandlers [private]

Definition at line 309 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

QMultiMap<const std::type_info *, Handler *> Utils::ObjectDispatcher< DispatchBase, Sender >::handlers [private]

Definition at line 310 of file ObjectDispatcher.h.

template<typename DispatchBase, typename Sender = void>

QList<Handler *> Utils::ObjectDispatcher< DispatchBase, Sender >::notHandledHandlers [private]

Definition at line 311 of file ObjectDispatcher.h.

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

Utils/ObjectDispatcher.h


Public Types
typedef Callable< void(const DispatchBase &)>	DispatchBaseHandler
typedef Callable< void(const DispatchBase &, Sender *)	DispatchBaseSenderHandler )
Public Member Functions
	ObjectDispatcher ()
	Default constructor.
	~ObjectDispatcher ()
	Destructor. Frees all allocated memory.
void	registerCatchAllHandler (const DispatchBaseHandler &handler)
	Register a non-member/static-member function as a catch-all handler.
void	registerCatchAllHandler (const DispatchBaseSenderHandler &handler)
	Register a member function as a catch-all handler.
template<typename T>
void	registerTypeHandler (const Callable< void(const T &)> &handler)
	Register a non-member/static-member function as type handler.
template<typename T>
void	registerTypeHandler (const Callable< void(const T &, Sender *)> &handler)
	Register a member function as type handler.
template<typename T>
void	unregisterTypeHandler (const Callable< void(const T &)> &handler)
	Unregister a non-member/static-member function as type handler.
template<typename T>
void	unregisterTypeHandler (const Callable< void(const T &, Sender *)> &handler)
	Unregister a member function as type handler.
void	registerNotHandledHandler (const DispatchBaseHandler &handler)
	Register a non-member/static-member function as type handler.
void	registerNotHandledHandler (const DispatchBaseSenderHandler &handler)
	Register a member function as type handler.
bool	dispatch (const DispatchBase &object, Sender *sender=0)
	Dispatch object to the corresponding registered handlers.
Private Member Functions
void	doRegisterCatchAllHandler (Handler *handler)
	Helper to register handler as a type handler for T.
template<typename T>
void	doRegisterHandler (Handler *handler)
	Helper to register handler as a type handler for T.
template<typename T>
void	doUnregisterHandler (Handler *handler)
	Helper to register handler as a type handler for T.
void	doRegisterNotHandledHandler (Handler *handler)
	Helper to register handler as a type handler for T.
void	dispatchToCatchAllHandlers (const DispatchBase &object, Sender *sender)
	Helper to dispatch to all the catch-all registered handlers.
bool	dispatchToTypeHandlers (const DispatchBase &object, Sender *sender)
	Helper to dispatch to all type handlers matching typeid (object).
void	dispatchToNotHandledHandlers (const DispatchBase &object, Sender *sender)
	Helper to dispatch to all not-handled handlers.
Private Attributes
QList< Handler * >	catchAllHandlers
QMultiMap< const std::type_info , Handler >	handlers
QList< Handler * >	notHandledHandlers
Classes
struct	Handler
	Interface to a Handler wrapper. More...
class	TypeHandler
class	TypeHandlerWithSender

Utils::ObjectDispatcher< DispatchBase, Sender > Class Template Reference

Detailed Description

template<typename DispatchBase, typename Sender = void> class Utils::ObjectDispatcher< DispatchBase, Sender >

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Classes

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

template<typename DispatchBase, typename Sender = void>
class Utils::ObjectDispatcher< DispatchBase, Sender >