Decorator class for wrapping indexes with a cache. More...

Inheritance diagram for meta::index::cached_index< Index, Cache >:

Public Types
using	primary_key_type = typename Index::primary_key_type

using	secondary_key_type = typename Index::secondary_key_type

using	postings_data_type = typename Index::postings_data_type

Public Member Functions
template<class... Args>
	cached_index (cpptoml::table &config, Args &&...args)
	Forwarding constructor: construct the Index part using the config, but then forward the additional arguments to the underlying cache. More...

virtual std::shared_ptr< postings_data_type >	search_primary (primary_key_type p_id) const override
	Overload for search_primary() that first attempts to find the result in the cache. More...

void	clear_cache ()
	Clears the cache for the index. More...

Private Attributes
Cache< primary_key_type, std::shared_ptr< postings_data_type > >	cache_
	The internal cache object.

Detailed Description

Decorator class for wrapping indexes with a cache.

Like other indexes, you shouldn't construct this directly, but rather use make_index().

Constructor & Destructor Documentation

template<class Index , template< class, class > class Cache>

template<class... Args>

meta::index::cached_index< Index, Cache >::cached_index	(	cpptoml::table &	config,
		Args &&...	args
	)

Forwarding constructor: construct the Index part using the config, but then forward the additional arguments to the underlying cache.

Parameters

config	the configuration that specifies how the index should be constructed
args	The remaining arguments to send to the Cache constructor

template<class Index , template< class, class > class Cache>

auto meta::index::cached_index< Index, Cache >::search_primary ( primary_key_type p_id ) const

overridevirtual

Overload for search_primary() that first attempts to find the result in the cache.

Failing that, it will invoke the base class search_primary(), store the result in the cache, and then return the value.

Parameters

p_id	the primary key to search the postings file for

template<class Index , template< class, class > class Cache>

void meta::index::cached_index< Index, Cache >::clear_cache ( )

Clears the cache for the index.

Useful if you're using something like no-evict cache and want to reclaim memory.

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