3 #ifndef CDSLIB_CONTAINER_STRIPED_MAP_H
4 #define CDSLIB_CONTAINER_STRIPED_MAP_H
7 #include <cds/container/striped_set.h>
8 #include <cds/container/striped_set/adapter.h>
9 #include <cds/details/binary_functor_wrapper.h>
11 namespace cds { namespace container {
15 template <class Container, typename... Options>
16 class make_striped_map
18 typedef StripedSet< Container, Options...> billet;
19 typedef typename billet::options billet_options;
20 typedef typename billet_options::hash billet_hash;
22 typedef typename Container::value_type pair_type;
23 typedef typename pair_type::first_type key_type;
25 struct options: public billet_options {
26 struct hash: public billet_hash {
27 size_t operator()( pair_type const& v ) const
29 return billet_hash::operator()( v.first );
33 size_t operator()( Q const& v ) const
35 return billet_hash::operator()( v );
41 typedef StripedSet< Container, cds::opt::type_traits< options > > type ; ///< metafunction result
47 /** @ingroup cds_nonintrusive_map
50 - [2008] Maurice Herlihy, Nir Shavit "The Art of Multiprocessor Programming"
52 Lock striping is very simple technique.
53 The map consists of the bucket table and the array of locks.
54 Initially, the capacity of lock array and bucket table is the same.
55 When the map is resized, bucket table capacity will be doubled but lock array will not.
56 The lock \p i protects each bucket \p j, where <tt> j = i mod L </tt>,
57 where \p L - the size of lock array.
60 - \p Container - the container class that is used as bucket entry. The \p Container class should support
61 an uniform interface described below.
62 - \p Options - options
64 The \p %StripedMap class does not exactly specify the type of container that should be used as a \p Container bucket.
65 Instead, the class supports different container type for the bucket, for exampe, \p std::list, \p std::map and others.
67 Remember that \p %StripedMap class algorithm ensures sequential blocking access to its bucket through the mutex type you specify
68 among \p Options template arguments.
71 - \p opt::mutex_policy - concurrent access policy.
72 Available policies: \p intrusive::striped_set::striping, \p intrusive::striped_set::refinable.
73 Default is %striped_set::striping.
74 - \p opt::hash - hash functor. Default option value see <tt>opt::v::hash_selector<opt::none> </tt>
75 which selects default hash functor for your compiler.
76 - \p opt::compare - key comparison functor. No default functor is provided.
77 If the option is not specified, the \p %opt::less is used.
78 - \p opt::less - specifies binary predicate used for key comparison. Default is \p std::less<T>.
79 - \p opt::item_counter - item counter type. Default is \p atomicity::item_counter since some operation on the counter is performed
80 without locks. Note that item counting is an essential part of the map algorithm, so dummy counter
81 like as \p atomicity::empty_item_counter is not suitable.
82 - \p opt::allocator - the allocator type using for memory allocation of bucket table and lock array. Default is \ref CDS_DEFAULT_ALLOCATOR.
83 - \p opt::resizing_policy - the resizing policy that is a functor that decides when to resize the hash map.
84 Default option value depends on bucket container type:
85 for sequential containers like \p std::list, \p std::vector the resizing policy is <tt>striped_set::load_factor_resizing<4> </tt>;
86 for other type of containers like \p std::map, \p std::unordered_map the resizing policy is \p striped_set::no_resizing.
87 See \ref cds_striped_resizing_policy "available resizing policy".
88 Note that the choose of resizing policy depends of \p Container type:
89 for sequential containers like \p std::list, \p std::vector and so on, right choosing of the policy can
90 significantly improve performance.
91 For other, non-sequential types of \p Container (like a \p std::map)
92 the resizing policy is not so important.
93 - \p opt::copy_policy - the copy policy which is used to copy items from the old map to the new one when resizing.
94 The policy can be optionally used in adapted bucket container for performance reasons of resizing.
95 The detail of copy algorithm depends on type of bucket container and explains below.
97 \p %opt::compare or \p %opt::less options are used only in some \p Container class for searching an item.
98 \p %opt::compare option has the highest priority: if \p %opt::compare is specified, \p %opt::less is not used.
100 You can pass other option that would be passed to <tt>adapt</tt> metafunction, see below.
102 <b>Internal details</b>
104 The \p %StripedMap class cannot utilize the \p Container container specified directly, but only its adapted variant which
105 supports an unified interface. Internally, the adaptation is made via \p striped_set::adapt metafunction that wraps bucket container
106 and provides the unified bucket interface suitable for \p %StripedMap. Such adaptation is completely transparent for you -
107 you don't need to call \p adapt metafunction directly, \p %StripedMap class's internal machinery itself invokes appropriate
108 \p adapt metafunction to adjust your \p Container container class to \p %StripedMap bucket's internal interface.
109 All you need is to include a right header before <tt>striped_hash_map.h</tt>.
111 By default, <tt>striped_set::adapt<AnyContainer, Options...> </tt> metafunction does not make any wrapping to \p AnyContainer,
112 so, the result <tt>striped_set::adapt<AnyContainer, Options...>::type </tt> is the same as \p AnyContainer.
113 However, there are a lot of specializations of \p adapt for well-known containers, see table below.
114 Any of this specialization wraps corresponding container making it suitable for the map's bucket.
115 Remember, you should include the proper header file for \p adapt <b>before</b> <tt>striped_map.h</tt>.
119 <th>.h-file for \p adapt</th>
124 <td> \p std::list</td>
125 <td><tt><cds/container/striped_map/std_list.h></tt></td>
127 #include <cds/container/striped_map/std_list.h>
128 #include <cds/container/striped_hash_map.h>
129 typedef cds::container::StripedMap<
130 std::list< std::pair< const Key, V > >,
131 cds::opt::less< std::less<Key> >
136 The type of values stored in the \p std::list must be <tt> std::pair< const Key, V > </tt>, where \p Key - key type, and \p V - value type
137 The list is ordered by key \p Key.
138 Template argument pack \p Options <b>must</b> contain \p cds::opt::less or \p cds::opt::compare for type \p Key stored in the list.
142 <td> \p std::map</td>
143 <td><tt><cds/container/striped_map/std_map.h></tt></td>
145 #include <cds/container/striped_map/std_map.h>
146 #include <cds/container/striped_hash_map.h>
147 typedef cds::container::StripedMap<
148 std::map< Key, T, std::less<Key> >
156 <td> \p std::unordered_map</td>
157 <td><tt><cds/container/striped_map/std_hash_map.h></tt></td>
159 #include <cds/container/striped_map/std_hash_map.h>
160 #include <cds/container/striped_hash_map.h>
161 typedef cds::container::StripedMap<
171 You should provide two different hash function \p h1 and \p h2 - one for std::unordered_map and other for \p %StripedMap.
172 For the best result, \p h1 and \p h2 must be orthogonal i.e. <tt> h1(X) != h2(X) </tt> for any value \p X of type \p Key.
176 <td> \p boost::container::slist</td>
177 <td><tt><cds/container/striped_map/boost_slist.h></tt></td>
179 #include <cds/container/hash_smap/boost_slist.h>
180 #include <cds/container/striped_hash_map.h>
181 typedef cds::container::StripedMap<
182 boost::container::slist< std::pair< const Key, T > >
187 The type of values stored in the \p boost::container::slist must be <tt> std::pair< const Key, T > </tt>,
188 where \p Key - key type, and \p T - value type. The list is ordered.
189 \p Options <b>must</b> contain \p cds::opt::less or \p cds::opt::compare.
193 <td> \p boost::container::list</td>
194 <td><tt><cds/container/striped_map/boost_list.h></tt></td>
196 #include <cds/container/striped_map/boost_list.h>
197 #include <cds/container/striped_hash_map.h>
198 typedef cds::container::StripedMap<
199 boost::container::list< std::pair< const Key, T > >
204 The type of values stored in the \p boost::container::list must be <tt> std::pair< const Key, T > </tt>,
205 where \p Key - key type, and \p T - value type. The list is ordered.
206 \p Options <b>must</b> contain \p cds::opt::less or \p cds::opt::compare.
210 <td> \p boost::container::map</td>
211 <td><tt><cds/container/striped_map/boost_map.h></tt></td>
213 #include <cds/container/striped_map/boost_map.h>
214 #include <cds/container/striped_hash_map.h>
215 typedef cds::container::StripedMap<
216 boost::container::map< Key, T, std::pair< const Key, T> >
224 <td> \p boost::container::flat_map</td>
225 <td><tt><cds/container/striped_map/boost_flat_map.h></tt></td>
227 #include <cds/container/striped_map/boost_flat_map.h>
228 #include <cds/container/striped_hash_map.h>
229 typedef cds::container::StripedMap<
230 boost::container::flat_map< Key, T,
231 std::less< std::pair< const Key, T> >
240 <td> \p boost::unordered_map</td>
241 <td><tt><cds/container/striped_map/boost_unordered_map.h></tt></td>
243 #include <cds/container/striped_map/boost_unordered_map.h>
244 #include <cds/container/refinable_hash_map.h>
245 typedef cds::container::StripedMap<
246 boost::unordered_map< Key, T, boost::hash<Key>, std::equal_to<Key> >
256 You can use another container type as map's bucket.
257 Suppose, you have a container class \p MyBestContainer and you want to integrate it with \p %StripedMap as bucket type.
258 There are two possibility:
259 - either your \p MyBestContainer class has native support of bucket's interface;
260 in this case, you can use default <tt>striped_set::adapt</tt> metafunction;
261 - or your \p MyBestContainer class does not support bucket's interface, which means, that you should develop a specialization
262 <tt>cds::container::striped_set::adapt<MyBestContainer> </tt> metafunction providing necessary interface.
264 The <tt>striped_set::adapt< Container, Options... ></tt> metafunction has two template argument:
265 - \p Container is the class that should be used as the bucket, for example, <tt>std::list< std::pair< Key, T > ></tt>.
266 - \p Options pack is the options from \p %StripedMap declaration. The \p adapt metafunction can use
267 any option from \p Options for its internal use. For example, a \p compare option can be passed to \p adapt
268 metafunction via \p Options argument of \p %StripedMap declaration.
270 See striped_set::adapt metafunction for the description of interface that the bucket container must provide
271 to be \p %StripedMap compatible.
274 There are three predefined copy policy:
275 - \p cds::container::striped_set::copy_item - copy item from old bucket to new one when resizing using copy ctor. It is default policy for
276 any compiler that do not support move semantics
277 - \p cds::container::striped_set::move_item - move item from old bucket to new one when resizing using move semantics. It is default policy for
278 any compiler that support move semantics. If compiler does not support move semantics, the move policy is the same as \p copy_item
279 - \p cds::container::striped_set::swap_item - copy item from old bucket to new one when resizing using \p std::swap. Not all containers support
280 this copy policy, see details in table below.
282 You can define your own copy policy specifically for your case.
283 Note, right copy policy can significantly improve the performance of resizing.
298 std::list< std::pair<const Key, T> >& list,
299 std::list<std::pair<const Key, T> >::iterator itInsert,
300 std::list<std::pair<const Key, T> >::iterator itWhat )
302 list.insert( itInsert, *itWhat );
307 // The type T stored in the list must be swappable
310 std::list< std::pair<const Key, T> >& list,
311 std::list<std::pair<const Key, T> >::iterator itInsert,
312 std::list<std::pair<const Key, T> >::iterator itWhat )
314 std::pair<Key, T> newVal( itWhat->first, T() );
315 std::swap( list.insert( itInsert, newVal )->second, itWhat->second );
322 std::list< std::pair<const Key, T> >& list,
323 std::list<std::pair<const Key, T> >::iterator itInsert,
324 std::list<std::pair<const Key, T> >::iterator itWhat )
326 list.insert( itInsert, std::move( *itWhat ) );
334 - \p std::unordered_map
335 - \p boost::container::map
336 - \p boost::container::flat_map
337 - \p boost::unordered_map
341 void operator()( std::map< Key, T>& map, std::map<Key, T>::iterator itWhat )
343 map.insert( *itWhat );
349 void operator()( std::map< Key, T>& map, std::map<Key, T>::iterator itWhat )
353 std::map::value_type( itWhat->first, T() ) ).first->second
358 \p T type must be swappable.
362 void operator()( std::map< Key, T>& map, std::map<Key, T>::iterator itWhat )
364 map.insert( std::move( *itWhat ));
369 <td> \p boost::container::slist</td>
373 bc::slist< std::pair<const Key, T> >& list,
374 bc::slist<std::pair<const Key, T> >::iterator itInsert,
375 bc::slist<std::pair<const Key, T> >::iterator itWhat )
377 list.insert_after( itInsert, *itWhat );
382 // The type T stored in the list must be swappable
385 bc::slist< std::pair<const Key, T> >& list,
386 bc::slist<std::pair<const Key, T> >::iterator itInsert,
387 bc::slist<std::pair<const Key, T> >::iterator itWhat )
389 std::pair<Key, T> newVal( itWhat->first, T() );
390 std::swap( list.insert( itInsert, newVal )->second, itWhat->second );
397 bc::slist< std::pair<const Key, T> >& list,
398 bc::slist<std::pair<const Key, T> >::iterator itInsert,
399 bc::slist<std::pair<const Key, T> >::iterator itWhat )
401 list.insert_after( itInsert, std::move( *itWhat ) );
408 <b>Advanced functions</b>
410 The library provides some advanced functions like \p erase_with(), \p find_with(),
411 that cannot be supported by all underlying containers.
412 The table below shows whether underlying container supports those functions
413 (the sign "+" means "container supports the function"):
418 <th>\p find_with</th>
419 <th>\p erse_with</th>
422 <td> \p std::list</td>
427 <td> \p std::map</td>
432 <td> \p std::unordered_map</td>
437 <td> \p boost::container::slist</td>
442 <td> \p boost::container::list</td>
447 <td> \p boost::container::map</td>
452 <td> \p boost::container::flat_map</td>
457 <td> \p boost::unordered_map</td>
464 template <class Container, typename... Options>
466 #ifdef CDS_DOXYGEN_INVOKED
467 : protected StripedSet<Container, Options...>
469 : protected details::make_striped_map< Container, Options...>::type
473 typedef typename details::make_striped_map< Container, Options...>::type base_class;
478 typedef typename base_class::default_options default_options;
479 typedef typename base_class::options options;
482 typedef Container underlying_container_type ; ///< original intrusive container type for the bucket
483 typedef typename base_class::bucket_type bucket_type ; ///< container type adapted for hash set
484 typedef typename bucket_type::value_type value_type ; ///< pair type (<tt> std::pair<key_type const, mapped_type> </tt>)
485 typedef typename value_type::first_type key_type ; ///< key type
486 typedef typename value_type::second_type mapped_type ; ///< mapped type
488 typedef typename base_class::hash hash ; ///< Hash functor
489 typedef typename base_class::item_counter item_counter ; ///< Item counter
490 typedef typename base_class::resizing_policy resizing_policy ; ///< Resizing policy
491 typedef typename base_class::allocator_type allocator_type ; ///< allocator type specified in options.
492 typedef typename base_class::mutex_policy mutex_policy ; ///< Mutex policy
495 typedef cds::container::striped_set::implementation_tag implementation_tag;
499 typedef typename base_class::scoped_cell_lock scoped_cell_lock;
500 typedef typename base_class::scoped_full_lock scoped_full_lock;
501 typedef typename base_class::scoped_resize_lock scoped_resize_lock;
506 struct key_accessor {
507 key_type const& operator()( value_type const& p ) const
515 /// Default ctor. The initial capacity is 16.
520 /// Ctor with initial capacity specified
522 size_t nCapacity ///< Initial size of bucket table and lock array. Must be power of two, the minimum is 16.
523 ) : base_class( nCapacity )
526 /// Ctor with resizing policy (copy semantics)
528 This constructor initializes m_ResizingPolicy member with copy of \p resizingPolicy parameter
531 size_t nCapacity ///< Initial size of bucket table and lock array. Must be power of two, the minimum is 16.
532 ,resizing_policy const& resizingPolicy ///< Resizing policy
533 ) : base_class( nCapacity, resizingPolicy )
536 /// Ctor with resizing policy (move semantics)
538 This constructor initializes m_ResizingPolicy member moving \p resizingPolicy parameter
539 Move semantics is used. Available only for the compilers that supports C++11 rvalue reference.
542 size_t nCapacity ///< Initial size of bucket table and lock array. Must be power of two, the minimum is 16.
543 ,resizing_policy&& resizingPolicy ///< Resizing policy
544 ) : base_class( nCapacity, std::forward<resizing_policy>(resizingPolicy) )
547 /// Destructor destroys internal data
552 /// Inserts new node with key and default value
554 The function creates a node with \p key and default value, and then inserts the node created into the map.
557 - The \p key_type should be constructible from a value of type \p K.
558 In trivial case, \p K is equal to \p key_type.
559 - The \p mapped_type should be default-constructible.
561 Returns \p true if inserting successful, \p false otherwise.
563 template <typename K>
564 bool insert( K const& key )
566 return insert_with( key, [](value_type&){} );
571 The function creates a node with copy of \p val value
572 and then inserts the node created into the map.
575 - The \p key_type should be constructible from \p key of type \p K.
576 - The \p mapped_type should be constructible from \p val of type \p V.
578 Returns \p true if \p val is inserted into the set, \p false otherwise.
580 template <typename K, typename V>
581 bool insert( K const& key, V const& val )
583 return insert_with( key, [&val](value_type& item) { item.second = val ; } );
586 /// Inserts new node and initialize it by a functor
588 This function inserts new node with key \p key and if inserting is successful then it calls
589 \p func functor with signature
592 void operator()( value_type& item );
596 The argument \p item of user-defined functor \p func is the reference
597 to the map's item inserted:
598 - <tt>item.first</tt> is a const reference to item's key that cannot be changed.
599 - <tt>item.second</tt> is a reference to item's value that may be changed.
601 The key_type should be constructible from value of type \p K.
603 The function allows to split creating of new item into two part:
604 - create item from \p key;
605 - insert new item into the map;
606 - if inserting is successful, initialize the value of item by calling \p func functor
608 This can be useful if complete initialization of object of \p mapped_type is heavyweight and
609 it is preferable that the initialization should be completed only if inserting is successful.
611 template <typename K, typename Func>
612 bool insert_with( const K& key, Func func )
614 return base_class::insert( key, func );
617 /// For key \p key inserts data of type \p mapped_type created in-place from \p args
619 Returns \p true if inserting successful, \p false otherwise.
621 template <typename K, typename... Args>
622 bool emplace( K&& key, Args&&... args )
626 size_t nHash = base_class::hashing( std::forward<K>(key));
627 bucket_type * pBucket;
629 scoped_cell_lock sl( base_class::m_MutexPolicy, nHash );
630 pBucket = base_class::bucket( nHash );
632 bOk = pBucket->emplace( std::forward<K>(key), std::forward<Args>(args)...);
633 bResize = bOk && base_class::m_ResizingPolicy( ++base_class::m_ItemCounter, *this, *pBucket );
637 base_class::resize();
642 /// Ensures that the \p key exists in the map
644 The operation performs inserting or changing data with lock-free manner.
646 If the \p key not found in the map, then the new item created from \p key
647 is inserted into the map (note that in this case the \p key_type should be
648 constructible from type \p K).
649 Otherwise, the functor \p func is called with item found.
650 The functor \p Func may be a function with signature:
652 void func( bool bNew, value_type& item );
657 void operator()( bool bNew, value_type& item );
662 - \p bNew - \p true if the item has been inserted, \p false otherwise
663 - \p item - item of the list
665 The functor may change any fields of the \p item.second that is \p mapped_type.
667 Returns <tt> std::pair<bool, bool> </tt> where \p first is true if operation is successfull,
668 \p second is true if new item has been added or \p false if the item with \p key
669 already is in the list.
671 template <typename K, typename Func>
672 std::pair<bool, bool> ensure( K const& key, Func func )
674 std::pair<bool, bool> result;
676 size_t nHash = base_class::hashing( key );
677 bucket_type * pBucket;
679 scoped_cell_lock sl( base_class::m_MutexPolicy, nHash );
680 pBucket = base_class::bucket( nHash );
682 result = pBucket->ensure( key, func );
683 bResize = result.first && result.second && base_class::m_ResizingPolicy( ++base_class::m_ItemCounter, *this, *pBucket );
687 base_class::resize();
691 /// Delete \p key from the map
692 /** \anchor cds_nonintrusive_StripedMap_erase
694 Return \p true if \p key is found and deleted, \p false otherwise
696 template <typename K>
697 bool erase( K const& key )
699 return base_class::erase( key );
702 /// Deletes the item from the map using \p pred predicate for searching
704 The function is an analog of \ref cds_nonintrusive_StripedMap_erase "erase(K const&)"
705 but \p pred is used for key comparing.
706 \p Less functor has the interface like \p std::less.
707 \p pred must imply the same element order as the comparator used for building the map.
709 @note This function is enabled if the compiler supports C++11
710 default template arguments for function template <b>and</b> the underlying container
711 supports \p %erase_with feature.
713 template < typename K, typename Less
714 ,typename Bucket = bucket_type, typename = typename std::enable_if< Bucket::has_erase_with >::type >
715 bool erase_with( K const& key, Less pred )
717 return erase_with( key, pred, [](value_type const&) {} );
720 /// Delete \p key from the map
721 /** \anchor cds_nonintrusive_StripedMap_erase_func
723 The function searches an item with key \p key, calls \p f functor
724 and deletes the item. If \p key is not found, the functor is not called.
726 The functor \p Func interface:
729 void operator()(value_type& item) { ... }
733 Return \p true if key is found and deleted, \p false otherwise
735 template <typename K, typename Func>
736 bool erase( K const& key, Func f )
738 return base_class::erase( key, f );
741 /// Deletes the item from the map using \p pred predicate for searching
743 The function is an analog of \ref cds_nonintrusive_StripedMap_erase_func "erase(K const&, Func)"
744 but \p pred is used for key comparing.
745 \p Less functor has the interface like \p std::less.
746 \p pred must imply the same element order as the comparator used for building the map.
748 @note This function is enabled if the compiler supports C++11
749 default template arguments for function template <b>and</b> the underlying container
750 supports \p %erase_with feature.
752 template <typename K, typename Less, typename Func
753 ,typename Bucket = bucket_type, typename = typename std::enable_if< Bucket::has_erase_with >::type >
754 bool erase_with( K const& key, Less pred, Func f )
757 return base_class::erase_with( key, cds::details::predicate_wrapper< value_type, Less, key_accessor >(), f );
760 /// Find the key \p key
761 /** \anchor cds_nonintrusive_StripedMap_find_func
763 The function searches the item with key equal to \p key and calls the functor \p f for item found.
764 The interface of \p Func functor is:
767 void operator()( value_type& item );
770 where \p item is the item found.
772 The functor may change \p item.second.
774 The function returns \p true if \p key is found, \p false otherwise.
776 template <typename K, typename Func>
777 bool find( K const& key, Func f )
779 return base_class::find( key, [&f]( value_type& pair, K const& ) mutable { f(pair); } );
782 /// Find the key \p val using \p pred predicate
784 The function is an analog of \ref cds_nonintrusive_StripedMap_find_func "find(K const&, Func)"
785 but \p pred is used for key comparing
786 \p Less has the interface like \p std::less.
787 \p pred must imply the same element order as the comparator used for building the set.
789 @note This function is enabled if the compiler supports C++11
790 default template arguments for function template <b>and</b> the underlying container
791 supports \p %find_with feature.
793 template <typename K, typename Less, typename Func
794 ,typename Bucket = bucket_type, typename = typename std::enable_if< Bucket::has_find_with >::type >
795 bool find_with( K const& key, Less pred, Func f )
798 return base_class::find_with( key, cds::details::predicate_wrapper< value_type, Less, key_accessor >(),
799 [&f]( value_type& pair, K const& ) mutable { f(pair); } );
802 /// Find the key \p key
803 /** \anchor cds_nonintrusive_StripedMap_find_val
805 The function searches the item with key equal to \p key
806 and returns \p true if it is found, and \p false otherwise.
808 template <typename K>
809 bool find( K const& key )
811 return base_class::find( key );
814 /// Find the key \p val using \p pred predicate
816 The function is an analog of \ref cds_nonintrusive_StripedMap_find_val "find(K const&)"
817 but \p pred is used for key comparing
818 \p Less has the interface like \p std::less.
819 \p pred must imply the same element order as the comparator used for building the set.
821 @note This function is enabled if the compiler supports C++11
822 default template arguments for function template <b>and</b> the underlying container
823 supports \p %find_with feature.
825 template <typename K, typename Less
826 ,typename Bucket = bucket_type, typename = typename std::enable_if< Bucket::has_find_with >::type >
827 bool find_with( K const& key, Less pred )
830 return base_class::find_with( key, cds::details::predicate_wrapper< value_type, Less, key_accessor >() );
839 /// Checks if the map is empty
841 Emptiness is checked by item counting: if item count is zero then the map is empty.
845 return base_class::empty();
848 /// Returns item count in the map
851 return base_class::size();
854 /// Returns the size of hash table
856 The hash table size is non-constant and can be increased via resizing.
858 size_t bucket_count() const
860 return base_class::bucket_count();
863 /// Returns lock array size
865 The lock array size is constant.
867 size_t lock_count() const
869 return base_class::lock_count();
872 /// Returns resizing policy object
873 resizing_policy& get_resizing_policy()
875 return base_class::get_resizing_policy();
878 /// Returns resizing policy (const version)
879 resizing_policy const& get_resizing_policy() const
881 return base_class::get_resizing_policy();
885 }} // namespace cds::container
887 #endif // #ifndef CDSLIB_CONTAINER_STRIPED_MAP_H