Generic Cache
[UTIL]

Collaboration diagram for Generic Cache:

Files
file	ncbi_cache.hpp
	The NCBI C++ generic cache template.
Classes
struct	SCacheElement< TKey, TSize >
	Internal structure to hold cache elements. More...
struct	CCacheElement_Less< TCacheElementPtr >
	Compare cache elements by weight/order. More...
class	CCacheElement_Handler< TKey, TValue >
	Default (NOP) element handler. More...
class	CCache< TKey, TValue, THandler, TLock, TSize >
	Cache template. More...
class	CCacheException
	Exception thrown by CCache. More...
Typedefs
typedef CMutex	TCacheLock_Default
	Default cache lock.
Enumerations
enum	ECache_InsertFlag { eCache_CheckSize, eCache_CanInsert, eCache_NeedCleanup, eCache_DoNotCache }
	Flag indicating if an element can be inserted into cache. More...
Functions
	CCache::CCache (TSizeType capacity, THandler *handler=new THandler())
	Create cache object with the given capacity.
	CCache::~CCache (void)
void	CCache::x_EraseElement (TCacheSet_I &set_iter, TCacheMap_I &map_iter)
void	CCache::x_EraseLast (void)
TCacheElement *	CCache::x_InsertElement (const TKeyType &key, TWeight weight)
void	CCache::x_UpdateElement (TCacheElement *elem)
TOrder	CCache::x_GetNextCounter (void)
void	CCache::x_PackElementIndex (void)
TOrder	CCache::Add (const TKeyType &key, const TValueType &value, TWeight weight=1, TAddFlags add_flags=0, EAddResult *result=NULL)
	Add new element to the cache or replace the existing value.
TValueType	CCache::operator[] (const TKeyType &key)
	Get cache element by the key.
TValueType	CCache::Get (const TKeyType &key, TGetFlags get_flags=0, EGetResult *result=NULL)
	Get an object from the cache by its key.
bool	CCache::Remove (const TKeyType &key)
	Remove element from cache. Do nothing if the key is not cached.
void	CCache::SetCapacity (TSizeType new_capacity)
	Set new capacity of the cache.
void	CCache::SetSize (TSizeType new_size)
	Truncate the cache leaving at most new_size elements.

---

Typedef Documentation

typedef CMutex TCacheLock_Default

Default cache lock. Definition at line 134 of file ncbi_cache.hpp.

---

Enumeration Type Documentation

enum ECache_InsertFlag

Flag indicating if an element can be inserted into cache. Enumerator: eCache_CheckSize  Insert the element after checking max cache size. eCache_CanInsert  The element can be inserted. eCache_NeedCleanup  Need to cleanup cache before inserting the element. eCache_DoNotCache  The element can not be inserted (e.g. too big). Definition at line 96 of file ncbi_cache.hpp.

---

Function Documentation

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::TOrder CCache< TKey, TValue, THandler, TLock, TSize >::Add (  const TKeyType &  key, const TValueType &  value, TWeight  weight = 1, TAddFlags  add_flags = 0, EAddResult *  result = NULL )  [inherited]

Add new element to the cache or replace the existing value. Parameters: key  Element key value  Element value weight  Weight adjustment. The lifetime of each object in the cache is proportional to its weight. add_flags  Flags to control Add() behavior. result  Pointer to a variable to store operation result code to. Returns: Index of the new element in the cache. Definition at line 506 of file ncbi_cache.hpp. References CCache< TKey, TValue, THandler, TLock, TSize >::eAdd_NotInserted, CCache< TKey, TValue, THandler, TLock, TSize >::eAdd_Replaced, map_checker< Container >::end(), CCache< TKey, TValue, THandler, TLock, TSize >::fAdd_NoReplace, set< Key, Compare >::find(), map_checker< Container >::find(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheMap, CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock, and CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseElement().

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::CCache (  TSizeType  capacity, THandler *  handler = new THandler() )  [inherited]

Create cache object with the given capacity. Definition at line 326 of file ncbi_cache.hpp. References _ASSERT, CCache< TKey, TValue, THandler, TLock, TSize >::m_Handler, and auto_ptr< X >::reset().

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::TValueType CCache< TKey, TValue, THandler, TLock, TSize >::Get (  const TKeyType &  key, TGetFlags  get_flags = 0, EGetResult *  result = NULL )  [inherited]

Get an object from the cache by its key. Depending on flags create and cache a new value if the key is not found. If the flags do not allow creating new elements, throws an exception. Parameters: key  Element key get_flags  Flags to control element retrieval result  pointer to a variable to store the result code to. Returns: The value referenced by the key or a new value created by the handler's CreateValue(). Definition at line 589 of file ncbi_cache.hpp. References CCache< TKey, TValue, THandler, TLock, TSize >::eGet_Found, map_checker< Container >::end(), CCache< TKey, TValue, THandler, TLock, TSize >::fGet_NoTouch, map_checker< Container >::find(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheMap, CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock, and CCache< TKey, TValue, THandler, TLock, TSize >::x_UpdateElement().

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::TValueType CCache< TKey, TValue, THandler, TLock, TSize >::operator[] (  const TKeyType &  key  )  [inherited]

Get cache element by the key. If the key is not cached yet, the handler's CreateValue() will be called to create one and the new element will be stored in the cache. See also: Get() Definition at line 572 of file ncbi_cache.hpp. References map_checker< Container >::end(), map_checker< Container >::find(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheMap, CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock, and CCache< TKey, TValue, THandler, TLock, TSize >::x_UpdateElement().

template<class TKey, class TValue, class THandler, class TLock, class TSize> bool CCache< TKey, TValue, THandler, TLock, TSize >::Remove (  const TKeyType &  key  )  [inherited]

Remove element from cache. Do nothing if the key is not cached. Definition at line 630 of file ncbi_cache.hpp. References map_checker< Container >::end(), map_checker< Container >::find(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheMap, and CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock.

template<class TKey, class TValue, class THandler, class TLock, class TSize> void CCache< TKey, TValue, THandler, TLock, TSize >::SetCapacity (  TSizeType  new_capacity  )  [inherited]

Set new capacity of the cache. The number of elements in the cache may be reduced to match the new capacity. Parameters: new_capacity  new cache capacity, must be > 0. Definition at line 645 of file ncbi_cache.hpp. References CCache< TKey, TValue, THandler, TLock, TSize >::GetSize(), CCache< TKey, TValue, THandler, TLock, TSize >::m_Capacity, CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock, NCBI_THROW, and CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseLast().

template<class TKey, class TValue, class THandler, class TLock, class TSize> void CCache< TKey, TValue, THandler, TLock, TSize >::SetSize (  TSizeType  new_size  )  [inherited]

Truncate the cache leaving at most new_size elements. Does not affect cache capacity. If new_size is zero all elements will be removed. Definition at line 660 of file ncbi_cache.hpp. References CCache< TKey, TValue, THandler, TLock, TSize >::GetSize(), CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock, and CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseLast().

template<class TKey, class TValue, class THandler, class TLock, class TSize> void CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseElement (  TCacheSet_I &  set_iter, TCacheMap_I &  map_iter )  [private, inherited]

Definition at line 349 of file ncbi_cache.hpp. References _ASSERT, map_checker< Container >::end(), set< Key, Compare >::end(), set< Key, Compare >::erase(), map_checker< Container >::erase(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheMap, CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, and CCache< TKey, TValue, THandler, TLock, TSize >::m_Handler. Referenced by CCache< TKey, TValue, THandler, TLock, TSize >::Add(), and CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseLast().

template<class TKey, class TValue, class THandler, class TLock, class TSize> void CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseLast (  void   )  [private, inherited]

Definition at line 365 of file ncbi_cache.hpp. References _ASSERT, set< Key, Compare >::begin(), set< Key, Compare >::empty(), map_checker< Container >::find(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheMap, CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, and CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseElement(). Referenced by CCache< TKey, TValue, THandler, TLock, TSize >::SetCapacity(), CCache< TKey, TValue, THandler, TLock, TSize >::SetSize(), and CCache< TKey, TValue, THandler, TLock, TSize >::~CCache().

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::TOrder CCache< TKey, TValue, THandler, TLock, TSize >::x_GetNextCounter (  void   )  [private, inherited]

Definition at line 419 of file ncbi_cache.hpp. References CCache< TKey, TValue, THandler, TLock, TSize >::m_Counter, and CCache< TKey, TValue, THandler, TLock, TSize >::x_PackElementIndex(). Referenced by CCache< TKey, TValue, THandler, TLock, TSize >::x_InsertElement(), and CCache< TKey, TValue, THandler, TLock, TSize >::x_UpdateElement().

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::TCacheElement * CCache< TKey, TValue, THandler, TLock, TSize >::x_InsertElement (  const TKeyType &  key, TWeight  weight )  [private, inherited]

Definition at line 376 of file ncbi_cache.hpp. References set< Key, Compare >::insert(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, NCBI_THROW, CCache< TKey, TValue, THandler, TLock, TSize >::x_GetBaseWeight(), CCache< TKey, TValue, THandler, TLock, TSize >::x_GetNextCounter(), and CCache< TKey, TValue, THandler, TLock, TSize >::x_PackElementIndex().

template<class TKey, class TValue, class THandler, class TLock, class TSize> void CCache< TKey, TValue, THandler, TLock, TSize >::x_PackElementIndex (  void   )  [private, inherited]

Definition at line 429 of file ncbi_cache.hpp. References set< Key, Compare >::begin(), set< Key, Compare >::empty(), ITERATE, CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, CCache< TKey, TValue, THandler, TLock, TSize >::m_Counter, SCacheElement< TKey, TSize >::m_Order, SCacheElement< TKey, TSize >::m_Weight, and NCBI_THROW. Referenced by CCache< TKey, TValue, THandler, TLock, TSize >::x_GetNextCounter(), CCache< TKey, TValue, THandler, TLock, TSize >::x_InsertElement(), and CCache< TKey, TValue, THandler, TLock, TSize >::x_UpdateElement().

template<class TKey, class TValue, class THandler, class TLock, class TSize> void CCache< TKey, TValue, THandler, TLock, TSize >::x_UpdateElement (  TCacheElement *  elem  )  [private, inherited]

Definition at line 400 of file ncbi_cache.hpp. References _ASSERT, set< Key, Compare >::end(), set< Key, Compare >::erase(), set< Key, Compare >::find(), set< Key, Compare >::insert(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, SCacheElement< TKey, TSize >::m_Order, SCacheElement< TKey, TSize >::m_Weight, CCache< TKey, TValue, THandler, TLock, TSize >::x_GetNextCounter(), and CCache< TKey, TValue, THandler, TLock, TSize >::x_PackElementIndex(). Referenced by CCache< TKey, TValue, THandler, TLock, TSize >::Get(), and CCache< TKey, TValue, THandler, TLock, TSize >::operator[]().

template<class TKey, class TValue, class THandler, class TLock, class TSize> CCache< TKey, TValue, THandler, TLock, TSize >::~CCache (  void   )  [inherited]

Definition at line 337 of file ncbi_cache.hpp. References set< Key, Compare >::empty(), CCache< TKey, TValue, THandler, TLock, TSize >::m_CacheSet, CCache< TKey, TValue, THandler, TLock, TSize >::m_Lock, and CCache< TKey, TValue, THandler, TLock, TSize >::x_EraseLast().

---