vlink::AbstractFactory< FilterT > Class Template Reference

Lazily allocates and caches AbstractObject instances keyed by FilterT. More...

#include <abstract_factory.h>

Collaboration diagram for vlink::AbstractFactory< FilterT >:

Public Member Functions
bool	has_object (Object *ptr) const
	Tests whether ptr corresponds to a live object created by this factory. More...
template<typename ObjectT >
std::shared_ptr< ObjectT >	get_object (const FilterT &filter)
	Looks up or creates the ObjectT registered against filter. More...

Protected Member Functions
	AbstractFactory ()
	Constructs an empty factory. More...
virtual	~AbstractFactory ()
	Destroys the factory and releases the cache. More...

Detailed Description

template<typename FilterT>
class vlink::AbstractFactory< FilterT >

Lazily allocates and caches AbstractObject instances keyed by FilterT.

Holds a std::map<FilterT, std::weak_ptr<Object>> so that multiple node peers requesting the same key reuse the same registration record. The returned std::shared_ptr carries a custom deleter that erases the map entry when the last owner releases the object, which keeps the lookup map free of stale weak_ptr slots.

Note

The factory itself is non-copyable and non-movable; share it through a singleton or a per-transport static instance.

Template Parameters

FilterT

Topic-key type (typically std::string).

Constructor & Destructor Documentation

AbstractFactory()

template<typename FilterT >

vlink::AbstractFactory< FilterT >::AbstractFactory ( )

inlineprotecteddefault

Constructs an empty factory.

~AbstractFactory()

template<typename FilterT >

vlink::AbstractFactory< FilterT >::~AbstractFactory ( )

inlineprotectedvirtualdefault

Destroys the factory and releases the cache.

Member Function Documentation

get_object()

template<typename FilterT >

template<typename ObjectT >

std::shared_ptr< ObjectT > vlink::AbstractFactory< FilterT >::get_object ( const FilterT &  filter )

inline

Looks up or creates the ObjectT registered against filter.

If the cached weak_ptr is still valid, the existing instance is shared with the caller. Otherwise a new ObjectT is allocated (outside the factory lock so its constructor can re-enter VLink safely), the resulting shared_ptr is given a deleter that removes the cache entry on destruction, and the value is stored back into the map.

Template Parameters

ObjectT

Concrete subclass of AbstractObject<FilterT> to allocate.

Parameters

filter

Key identifying the topic.

Returns

Shared ownership handle for the cached object.

has_object()

template<typename FilterT >

bool vlink::AbstractFactory< FilterT >::has_object ( Object *  ptr ) const

inline

Tests whether ptr corresponds to a live object created by this factory.

Parameters

ptr	Raw pointer to validate.

Returns

true when the object is still alive in this factory; false otherwise.

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

• include/vlink/impl/abstract_factory.h