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//$Id$
#ifndef CACHING_STRATEGIES_T_C
#define CACHING_STRATEGIES_T_C
#include "Caching_Strategies_T.h"
#if !defined (ACE_LACKS_PRAGMA_ONCE)
#define ACE_LACKS_PRAGMA_ONCE
#endif /* ACE_LACKS_PRAGMA_ONCE */
#if !defined (__ACE_INLINE__)
#include "Caching_Strategies_T.i"
#endif /* __ACE_INLINE__ */
ACE_RCSID(Web_Crawler, Caching_Strategies_T, "$Id$")
template<class CONTAINER> int
ACE_LRU_Caching_Strategy<CONTAINER>::clear_cache (CONTAINER &container)
{
// Check that the purge_percent is non-zero.
if (this->purge_percent_ == 0)
return 0;
// Also whether the number of entries in the cache is just one!
// Oops! then thers no way out but exiting. So return an error.
if (this->entries_ == 1)
return -1;
KEY key_to_remove;
VALUE value_to_remove;
ITEM *item = 0;
ATTRIBUTES min = 0;
// Return value.
int result = 0;
// Calculate the no of entries to remove form the cache depending
// upon the <purge_percent>.
int no_of_entries = (this->purge_percent_ / 100) * this->entries_;
// @@ Don't do this stuff below. Simply take the ceiling of the
// above <no_of_entries>.
// If the number of entries is less than 10 with the default percent
// being 10, the calculated no_pf_entries equals 0. So increment it
// so that atleast one entry gets purged.
if (no_of_entries == 0)
{
if (container.current_size () >= 1)
no_of_entries = 1;
}
for (int i = 0; i < no_of_entries ; ++i)
{
ITERATOR iter (container);
// The iterator moves thru the container searching for the entry with the
// lowest ATTRIBUTES.
for (min = (*iter).int_id_.second (), key_to_remove = (*iter).ext_id_, value_to_remove = (*iter).int_id_;
iter.next (item) != 0;
++iter)
{
// Ah! an item with lower ATTTRIBUTES...
if (min > (*iter).int_id_.second ())
{
min = (*iter).int_id_.second ();
key_to_remove = (*iter).ext_id_;
value_to_remove = (*iter).int_id_;
}
}
// @@ Remove this
ACE_DEBUG ((LM_DEBUG, "AUTO_PURGE\nLRU: before unbind: current_size %d\n", container.current_size ()));
// @@ Remove this svc_handler specific code!!
// Delete the dynamically allocated value object.
if (value_to_remove.first () != 0)
{
(value_to_remove.first ())->recycler (0, 0);
result = (value_to_remove.first ())->close();
if (result == -1)
return result;
}
// Remove the item from cache.
// @@ What happens to this result? You should stop on failure.
result = container.unbind (key_to_remove);
--this->entries_;
// @@ Remove this
ACE_DEBUG ((LM_DEBUG, "LRU:after unbind: result %d current_size %d\n", result, container.current_size ()));
}
return result;
}
////////////////////////////////////////////////////////////////////////////////////////////////
template<class CONTAINER> int
ACE_LFU_Caching_Strategy<CONTAINER>::clear_cache (CONTAINER &container)
{
// Check that the purge_percent is non-zero.
if (purge_percent_ == 0)
return 0;
// Also whether the number of entries in the cache is just one!
// Oops! then thers no way out but exiting. So return an error.
if (this->entries_ == 1)
return -1;
KEY key_to_remove;
VALUE value_to_remove;
ITEM *item = 0;
ATTRIBUTES min = 0;
// Return value.
int result = 0;
// Calculate the no of entries to remove form the cache depending upon the <purge_percent>.
int no_of_entries = (this->purge_percent_/100) * this->entries_;
// If the number of entries is less than 10 with the default percent
// being 10, the calculated no_pf_entries equals 0. So increment it
// so that atleast one entry gets purged.
if (no_of_entries == 0)
{
if (container.current_size () >= 1)
no_of_entries = 1;
}
for (int i = 0; i < no_of_entries ; ++i)
{
ITERATOR iter (container);
// The iterator moves thru the container searching for the entry with the
// lowest ATTRIBUTES.
for (min = (*iter).int_id_.second (), key_to_remove = (*iter).ext_id_, value_to_remove = (*iter).int_id_;
iter.next (item) != 0 ;
++iter)
{
// Ah! an item with lower ATTTRIBUTES...
if (min > (*iter).int_id_.second ())
{
min = (*iter).int_id_.second ();
key_to_remove = (*iter).ext_id_;
value_to_remove = (*iter).int_id_;
}
}
ACE_DEBUG ((LM_DEBUG, "AUTO_PURGE\nLFU: before unbind: current_size %d\n", container.current_size ()));
// Delete the dynamically allocated value object.
if (value_to_remove.first () != 0)
{
(value_to_remove.first ())->recycler (0, 0);
result = (value_to_remove.first ())->close();
if (result == -1)
return result;
}
// Remove the item from cache.
result = container.unbind (key_to_remove);
--this->entries_;
ACE_DEBUG ((LM_DEBUG, "LFU:after unbind: result %d current_size %d\n", result, container.current_size ()));
}
return result;
}
////////////////////////////////////////////////////////////////////////////////////////////////
template<class CONTAINER> int
ACE_FIFO_Caching_Strategy<CONTAINER>::clear_cache (CONTAINER &container)
{
// Check that the purge_percent is non-zero.
if (this->purge_percent_ == 0)
return 0;
// Also whether the number of entries in the cache is just one!
// Oops! then thers no way out but exiting. So return an error.
if (this->entries_ == 1)
return -1;
KEY key_to_remove;
VALUE value_to_remove;
ITEM *item = 0;
ATTRIBUTES min = 0;
// Return value.
int result = 0;
// Calculate the no of entries to remove form the cache depending upon the <purge_percent>.
int no_of_entries = (this->purge_percent_/100) * this->entries_;
// If the number of entries is less than 10 with the default percent
// being 10, the calculated no_pf_entries equals 0. So increment it
// so that atleast one entry gets purged.
if (no_of_entries == 0)
{
if (container.current_size () >= 1)
no_of_entries = 1;
}
for (int i = 0; i < no_of_entries ; ++i)
{
ITERATOR iter (container);
// The iterator moves thru the container searching for the entry with the
// lowest ATTRIBUTES.
for (min = (*iter).int_id_.second (), key_to_remove = (*iter).ext_id_, value_to_remove = (*iter).int_id_;
iter.next (item) != 0 ;
++iter)
{
// Ah! an item with lower ATTTRIBUTES...
if (min > (*iter).int_id_.second ())
{
min = (*iter).int_id_.second ();
key_to_remove = (*iter).ext_id_;
value_to_remove = (*iter).int_id_;
}
}
ACE_DEBUG ((LM_DEBUG, "AUTO_PURGE\nFIFO: before unbind: current_size %d\n", container.current_size ()));
// Delete the dynamically allocated value object.
if (value_to_remove.first () != 0)
{
(value_to_remove.first ())->recycler (0, 0);
result = (value_to_remove.first ())->close();
if (result == -1)
return result;
}
// Remove the item from cache.
result = container.unbind (key_to_remove);
--this->entries_;
ACE_DEBUG ((LM_DEBUG, "FIFO:after unbind: result %d current_size %d\n", result, container.current_size ()));
}
return result;
}
////////////////////////////////////////////////////////////////////////////////////////////////
template<class CONTAINER> int
ACE_Null_Caching_Strategy<CONTAINER>::clear_cache (CONTAINER &container)
{
return 0;
}
///////////////////////////////////////////////////////////////////////////////////////////////
ACE_ALLOC_HOOK_DEFINE(ACE_LRU_Caching_Strategy)
ACE_ALLOC_HOOK_DEFINE(ACE_LFU_Caching_Strategy)
ACE_ALLOC_HOOK_DEFINE(ACE_FIFO_Caching_Strategy)
ACE_ALLOC_HOOK_DEFINE(ACE_Null_Caching_Strategy)
#endif /* CACHING_STRATEGIES_T_C */
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