Cache< K, T > Class Template Reference

A general-purpose LRU-cache with a maximum capacity. More...

#include <Cache.h++>

Public Member Functions
	Cache (uint_t maxSize)
	Construct a new cache with the given maximum size. More...
virtual	~Cache ()
	Destructor. More...
void	put (K key, T *item)
	Put an item in the cache. More...
T *	get (K key) const
	Look up an item in the cache. More...
T *	operator[] (K key) const
	Index operator. More...
T *	take (K key)
	Remove an item from the cache, and return the item. More...
bool	remove (K key)
	Remove an item from the cache. More...
bool	contains (K key) const
	Test if the cache contains an item with the specified key. More...
void	clear ()
	Remove all items from the cache. More...
uint_t	getMaxSize () const
	Return the maximum size of the cache, i.e., the maximum number of items that the cache can hold. More...
uint_t	getSize () const
	Return the current size of the cache, i.e., the number of items in the cache. More...
bool	isEmpty () const
	Test if the cache is empty. More...

Protected Member Functions
virtual void	onRemove (K key, T *item)
	A method that is called whenever an item is being removed from the cache, but just before it has been deleted. More...

Detailed Description

template<typename K, typename T>
class ccxx::Cache< K, T >

A general-purpose LRU-cache with a maximum capacity.

The cache maintains a key/value map, and takes ownership of its items. If the cache is at full capacity when a new item is inserted, the least recently accessed item is removed to make room.

Whenever an item is removed from the cache as a result of a call to clear() remove(), put(), or the destructor, the onRemove() method is called just before the item is deleted.

Author

Mark Lindner

Constructor & Destructor Documentation

Cache()

Cache

(

uint_t

maxSize

)

Construct a new cache with the given maximum size.

Parameters

maxSize

The maximum number of items that the cache will hold. If 0, the value 1 will be used instead.

~Cache()

virtual ~Cache ( )

virtual

Destructor.

Clears the cache.

Member Function Documentation

clear()

void clear

(

)

Remove all items from the cache.

contains()

bool contains

(

K

key

)

const

Test if the cache contains an item with the specified key.

Parameters

key

The key.

Returns

true the cache contains an item with the specified key, false otherwise.

get()

T* get

(

K

key

)

const

Look up an item in the cache.

Parameters

key	The item key.

Returns

The item associated with the key, or NULL if no item with the specified key was found.

getMaxSize()

uint_t getMaxSize ( ) const

inline

Return the maximum size of the cache, i.e., the maximum number of items that the cache can hold.

getSize()

uint_t getSize ( ) const

inline

Return the current size of the cache, i.e., the number of items in the cache.

isEmpty()

bool isEmpty ( ) const

inline

Test if the cache is empty.

onRemove()

virtual void onRemove ( K  key, T *  item  )

protectedvirtual

A method that is called whenever an item is being removed from the cache, but just before it has been deleted.

The default implementation is a no-op. Subclasses may override this method to do any necessary cleanup of the item before it is deleted, but should not delete the item itself.

Parameters

key	The key for the item being removed.
item	The item being removed.

operator[]()

T* operator[] ( K  key ) const

inline

Index operator.

Equivalent to get().

put()

void put	(	K	key,
		T *	item
	)

Put an item in the cache.

Parameters

key	The key.
item	The item.

remove()

bool remove

(

K

key

)

Remove an item from the cache.

Parameters

key	The item key.

Returns

true if an item was removed, false if no item with the specified key was found.

take()

T* take

(

K

key

)

Remove an item from the cache, and return the item.

The onRemove() method is not called.

Parameters

key

The key.

Returns

The item associated with the key, or NULL if no item with the specified key was found.

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

• Cache.h++