A domain for objects which may be cached. More...

#include <elementary/memcore/Cacheable.hpp>

Inheritance diagram for MemCore::Cacheable:

Public Types
using	cachecounter_t = unsigned long
	The type to store repeated accesses to a cached object.

Public Types inherited from MemCore::ReferenceBase< Cacheable >
using	reference_domain_t = Cacheable
	The type of the base class.

using	SelfPtr_t = WeakPtr< Cacheable, Cacheable >
	Type for a pointer to this object itself.

Public Member Functions
	Cacheable (const WeakPtr< Creature > &C)
	Constructor.

virtual void	DeferredConstructor ()
	A virtual function that is called on the first strong referencing of a Cacheable object.

bool	isCached () const
	Check whether this object is managed by a cache queue.

bool	isUncached () const
	Check whether this object is managed by a cache queue.

bool	markAsUsed ()
	Mark this data object as being recently used.

virtual memsize_t	memsize () const =0
	Ask how many bytes this object occupies.

WeakPtr< CacheBase >	myCache () const
	Return the associated Cache object as known from the associated Creator, if any.

const WeakPtr< Creature > &	myCreator () const
	Return the associated Creator, if any.

int	NumberOfListEntries () const
	Count the number of entries here.

void	PreDestructor ()
	This class uses a predestructor to remove itself's size from the cache queue.

void	push_back (CacheQueue &Q)
	Put the current item onto the BACK of the given cache queue.

void	push_front (CacheQueue &Q)
	Put the current item onto the FRONT of the given cache queue.

void	setCreator (const WeakPtr< Creature > &C)
	Set and the creator.

Public Member Functions inherited from MemCore::ReferenceBase< Cacheable >
auto	getObjectCountID () const noexcept
	Get a unique ID for this object in the given domain.

bool	isIdentical (const WeakPtr< Cacheable, Cacheable > &PossibleSelf) const noexcept
	Check if this object is identical to the one used by the given pointer.

void	mkAutoDestructive ()
	Marks this object as being automatically destructed, e.g.

refcount_t	refcount () const noexcept
	The strong reference count.

	ReferenceBase (Cacheable *that) noexcept
	Constructor, initializes reference counter to zero.

const auto &	self () const
	Return weak pointer to the object self.

refcount_t	wrefcount () const noexcept
	The weak reference count.

Protected Member Functions
void	adjustCacheableSize (memsize_t memDiff)
	In case this object changes its size after insertion to the CacheQueue, call this function to adjust.

	~Cacheable ()
	Destructor.

Protected Member Functions inherited from MemCore::ReferenceBase< Cacheable >
virtual void	extremeUnction ()
	A virtual function that will be called just before the object is destroyed.

ReferenceBase &	operator= (const ReferenceBase &R)
	Protected assignment operator (should not be called).

void	suicide ()
	Delete this.

virtual	~ReferenceBase ()
	Virtual destructor.

Detailed Description

A domain for objects which may be cached.

Cacheable objects must be derived from this base class such that a WeakPtrImpl<Cacheable> may point to such object and becomes notified when the object is removed. Any child classes must overload the virtual memsize() to tell the Cache class how costly the storage of objects of this kind is. Note that the memsize() does not necessarily need to be given in bytes, any other unit is acceptable as long as the same is used consistently for all objects that are assigned to the same Cache object.

Member Function Documentation

◆ adjustCacheableSize()

void MemCore::Cacheable::adjustCacheableSize ( memsize_t memDiff )

protected

In case this object changes its size after insertion to the CacheQueue, call this function to adjust.

Alternatively, the cachequeue's memsize could be recomputed, but is much more effortsome.

Referenced by MemCore::MutableCacheable::adjustCurrentMemsize().

◆ DeferredConstructor()

void MemCore::Cacheable::DeferredConstructor ( )

virtual

A virtual function that is called on the first strong referencing of a Cacheable object.

This (usually) is not possible within the constructor, so it may be assumed that the object has been completely constructed. The implementation of this function may thus perform operations on the object which should be done automatically when objects of this kind are created, but they may be aware of the full object status which is not possible in the constructor.

◆ markAsUsed()

bool MemCore::Cacheable::markAsUsed ( )

Mark this data object as being recently used.

This is the same as touching the data, but touch() is also used in the Ageable class, so here we use another name to avoid confusion.

References myCache(), MemCore::CacheQueue::push_front(), and MemCore::ReferenceBase< Cacheable >::self().

Referenced by Wizt::AnemoneCreator< AnemoneInitializer >::produce().

◆ NumberOfListEntries()

int MemCore::Cacheable::NumberOfListEntries ( ) const

Count the number of entries here.

Never call this function, it is maximally slow.

◆ PreDestructor()

void MemCore::Cacheable::PreDestructor ( )

This class uses a predestructor to remove itself's size from the cache queue.

This could not be done in the "official" destructor itself because it depends on the call of the virtual function memsize() which is no longer available in the destructor.

References memsize(), myCache(), and MemCore::ReferenceBase< Cacheable >::self().

◆ push_back()

void MemCore::Cacheable::push_back ( CacheQueue & Q )

Put the current item onto the BACK of the given cache queue.

The memory sizes of the current and new cache queues will be adjusted.

References memsize().

Referenced by MemCore::CacheMultiQueue::adjust().

◆ push_front()

void MemCore::Cacheable::push_front ( CacheQueue & Q )

Put the current item onto the FRONT of the given cache queue.