tlx
btree_set< Key_, Compare_, Traits_, Alloc_ > Class Template Reference

Specialized B+ tree template class implementing STL's set container. More...

#include <btree_set.hpp>

Classes

struct  key_of_value
 Key Extractor Struct. More...
 

Public Types

Template Parameter Types
typedef Key_ key_type
 First template parameter: The key type of the B+ tree. More...
 
typedef Compare_ key_compare
 Second template parameter: Key comparison function object. More...
 
typedef Traits_ traits
 Third template parameter: Traits object used to define more parameters of the B+ tree. More...
 
typedef Alloc_ allocator_type
 Fourth template parameter: STL allocator. More...
 
Constructed Types
typedef key_type value_type
 Construct the set value_type: the key_type. More...
 
typedef btree_set< key_type, key_compare, traits, allocator_typeself
 Typedef of our own type. More...
 
typedef BTree< key_type, value_type, key_of_value, key_compare, traits, false, allocator_typebtree_impl
 Implementation type of the btree_base. More...
 
typedef btree_impl::value_compare value_compare
 Function class comparing two value_type keys. More...
 
typedef btree_impl::size_type size_type
 Size type used to count keys. More...
 
typedef btree_impl::tree_stats tree_stats
 Small structure containing statistics about the tree. More...
 
Iterators and Reverse Iterators
typedef btree_impl::iterator iterator
 STL-like iterator object for B+ tree items. More...
 
typedef btree_impl::const_iterator const_iterator
 STL-like iterator object for B+ tree items. More...
 
typedef btree_impl::reverse_iterator reverse_iterator
 create mutable reverse iterator by using STL magic More...
 
typedef btree_impl::const_reverse_iterator const_reverse_iterator
 create constant reverse iterator by using STL magic More...
 

Public Member Functions

Constructors and Destructor
 btree_set (const allocator_type &alloc=allocator_type())
 Default constructor initializing an empty B+ tree with the standard key comparison function. More...
 
 btree_set (const key_compare &kcf, const allocator_type &alloc=allocator_type())
 Constructor initializing an empty B+ tree with a special key comparison object. More...
 
template<class InputIterator >
 btree_set (InputIterator first, InputIterator last, const allocator_type &alloc=allocator_type())
 Constructor initializing a B+ tree with the range [first,last) More...
 
template<class InputIterator >
 btree_set (InputIterator first, InputIterator last, const key_compare &kcf, const allocator_type &alloc=allocator_type())
 Constructor initializing a B+ tree with the range [first,last) and a special key comparison object. More...
 
 ~btree_set ()
 Frees up all used B+ tree memory pages. More...
 
void swap (btree_set &from)
 Fast swapping of two identical B+ tree objects. More...
 
Key and Value Comparison Function Objects
key_compare key_comp () const
 Constant access to the key comparison object sorting the B+ tree. More...
 
value_compare value_comp () const
 Constant access to a constructed value_type comparison object. More...
 
Allocators
allocator_type get_allocator () const
 Return the base node allocator provided during construction. More...
 
Fast Destruction of the B+ Tree
void clear ()
 Frees all keys and all nodes of the tree. More...
 
STL Iterator Construction Functions
iterator begin ()
 Constructs a read/data-write iterator that points to the first slot in the first leaf of the B+ tree. More...
 
iterator end ()
 Constructs a read/data-write iterator that points to the first invalid slot in the last leaf of the B+ tree. More...
 
const_iterator begin () const
 Constructs a read-only constant iterator that points to the first slot in the first leaf of the B+ tree. More...
 
const_iterator end () const
 Constructs a read-only constant iterator that points to the first invalid slot in the last leaf of the B+ tree. More...
 
reverse_iterator rbegin ()
 Constructs a read/data-write reverse iterator that points to the first invalid slot in the last leaf of the B+ tree. More...
 
reverse_iterator rend ()
 Constructs a read/data-write reverse iterator that points to the first slot in the first leaf of the B+ tree. More...
 
const_reverse_iterator rbegin () const
 Constructs a read-only reverse iterator that points to the first invalid slot in the last leaf of the B+ tree. More...
 
const_reverse_iterator rend () const
 Constructs a read-only reverse iterator that points to the first slot in the first leaf of the B+ tree. More...
 
Access Functions to the Item Count
size_type size () const
 Return the number of keys in the B+ tree. More...
 
bool empty () const
 Returns true if there is at least one key in the B+ tree. More...
 
size_type max_size () const
 Returns the largest possible size of the B+ Tree. More...
 
const tree_statsget_stats () const
 Return a const reference to the current statistics. More...
 
STL Access Functions Querying the Tree by Descending to a Leaf
bool exists (const key_type &key) const
 Non-STL function checking whether a key is in the B+ tree. More...
 
iterator find (const key_type &key)
 Tries to locate a key in the B+ tree and returns an iterator to the key slot if found. More...
 
const_iterator find (const key_type &key) const
 Tries to locate a key in the B+ tree and returns an constant iterator to the key slot if found. More...
 
size_type count (const key_type &key) const
 Tries to locate a key in the B+ tree and returns the number of identical key entries found. More...
 
iterator lower_bound (const key_type &key)
 Searches the B+ tree and returns an iterator to the first pair equal to or greater than key, or end() if all keys are smaller. More...
 
const_iterator lower_bound (const key_type &key) const
 Searches the B+ tree and returns a constant iterator to the first pair equal to or greater than key, or end() if all keys are smaller. More...
 
iterator upper_bound (const key_type &key)
 Searches the B+ tree and returns an iterator to the first pair greater than key, or end() if all keys are smaller or equal. More...
 
const_iterator upper_bound (const key_type &key) const
 Searches the B+ tree and returns a constant iterator to the first pair greater than key, or end() if all keys are smaller or equal. More...
 
std::pair< iterator, iteratorequal_range (const key_type &key)
 Searches the B+ tree and returns both lower_bound() and upper_bound(). More...
 
std::pair< const_iterator, const_iteratorequal_range (const key_type &key) const
 Searches the B+ tree and returns both lower_bound() and upper_bound(). More...
 
B+ Tree Object Comparison Functions
bool operator== (const btree_set &other) const
 Equality relation of B+ trees of the same type. More...
 
bool operator!= (const btree_set &other) const
 Inequality relation. Based on operator==. More...
 
bool operator< (const btree_set &other) const
 Total ordering relation of B+ trees of the same type. More...
 
bool operator> (const btree_set &other) const
 Greater relation. Based on operator<. More...
 
bool operator<= (const btree_set &other) const
 Less-equal relation. Based on operator<. More...
 
bool operator>= (const btree_set &other) const
 Greater-equal relation. Based on operator<. More...
 
Fast Copy: Assign Operator and Copy Constructors
btree_setoperator= (const btree_set &other)
 Assignment operator. All the keys are copied. More...
 
 btree_set (const btree_set &other)
 Copy constructor. More...
 
Public Insertion Functions
std::pair< iterator, bool > insert (const key_type &x)
 Attempt to insert a key into the B+ tree. More...
 
iterator insert (iterator hint, const key_type &x)
 Attempt to insert a key into the B+ tree. More...
 
template<typename InputIterator >
void insert (InputIterator first, InputIterator last)
 Attempt to insert the range [first,last) of iterators dereferencing to key_type into the B+ tree. More...
 
template<typename Iterator >
void bulk_load (Iterator first, Iterator last)
 Bulk load a sorted range [first,last). More...
 
Public Erase Functions
bool erase_one (const key_type &key)
 Erases the key from the set. More...
 
size_type erase (const key_type &key)
 Erases all the key/data pairs associated with the given key. More...
 
void erase (iterator iter)
 Erase the key/data pair referenced by the iterator. More...
 
Verification of B+ Tree Invariants
void verify () const
 Run a thorough verification of all B+ tree invariants. More...
 

Public Attributes

 TLX_BTREE_FRIENDS
 The macro TLX_BTREE_FRIENDS can be used by outside class to access the B+ tree internals. More...
 

Static Public Attributes

Static Constant Options and Values of the B+ Tree
static const unsigned short leaf_slotmax
 Base B+ tree parameter: The number of key slots in each leaf. More...
 
static const unsigned short inner_slotmax
 Base B+ tree parameter: The number of key slots in each inner node, this can differ from slots in each leaf. More...
 
static const unsigned short leaf_slotmin
 Computed B+ tree parameter: The minimum number of key slots used in a leaf. More...
 
static const unsigned short inner_slotmin
 Computed B+ tree parameter: The minimum number of key slots used in an inner node. More...
 
static const bool self_verify
 Debug parameter: Enables expensive and thorough checking of the B+ tree invariants after each insert/erase operation. More...
 
static const bool debug
 Debug parameter: Prints out lots of debug information about how the algorithms change the tree. More...
 
static const bool allow_duplicates
 Operational parameter: Allow duplicate keys in the btree. More...
 

Private Attributes

Tree Implementation Object
btree_impl tree_
 The contained implementation object. More...
 

Detailed Description

template<typename Key_, typename Compare_ = std::less<Key_>, typename Traits_ = btree_default_traits<Key_, Key_>, typename Alloc_ = std::allocator<Key_>>
class tlx::btree_set< Key_, Compare_, Traits_, Alloc_ >

Specialized B+ tree template class implementing STL's set container.

Implements the STL set using a B+ tree. It can be used as a drop-in replacement for std::set. Not all asymptotic time requirements are met in theory. The class has a traits class defining B+ tree properties like slots and self-verification. Furthermore an allocator can be specified for tree nodes.

It is somewhat inefficient to implement a set using a B+ tree, a plain B tree would hold fewer copies of the keys.

Definition at line 49 of file btree_set.hpp.

Member Typedef Documentation

◆ allocator_type

typedef Alloc_ allocator_type

Fourth template parameter: STL allocator.

Definition at line 67 of file btree_set.hpp.

◆ btree_impl

Implementation type of the btree_base.

Definition at line 94 of file btree_set.hpp.

◆ const_iterator

typedef btree_impl::const_iterator const_iterator

STL-like iterator object for B+ tree items.

The iterator points to a specific slot number in a leaf.

Definition at line 152 of file btree_set.hpp.

◆ const_reverse_iterator

typedef btree_impl::const_reverse_iterator const_reverse_iterator

create constant reverse iterator by using STL magic

Definition at line 158 of file btree_set.hpp.

◆ iterator

typedef btree_impl::iterator iterator

STL-like iterator object for B+ tree items.

The iterator points to a specific slot number in a leaf.

Definition at line 148 of file btree_set.hpp.

◆ key_compare

typedef Compare_ key_compare

Second template parameter: Key comparison function object.

Definition at line 60 of file btree_set.hpp.

◆ key_type

typedef Key_ key_type

First template parameter: The key type of the B+ tree.

This is stored in inner nodes and leaves.

Definition at line 57 of file btree_set.hpp.

◆ reverse_iterator

typedef btree_impl::reverse_iterator reverse_iterator

create mutable reverse iterator by using STL magic

Definition at line 155 of file btree_set.hpp.

◆ self

Typedef of our own type.

Definition at line 84 of file btree_set.hpp.

◆ size_type

Size type used to count keys.

Definition at line 100 of file btree_set.hpp.

◆ traits

typedef Traits_ traits

Third template parameter: Traits object used to define more parameters of the B+ tree.

Definition at line 64 of file btree_set.hpp.

◆ tree_stats

typedef btree_impl::tree_stats tree_stats

Small structure containing statistics about the tree.

Definition at line 103 of file btree_set.hpp.

◆ value_compare

typedef btree_impl::value_compare value_compare

Function class comparing two value_type keys.

Definition at line 97 of file btree_set.hpp.

◆ value_type

Construct the set value_type: the key_type.

Definition at line 81 of file btree_set.hpp.

Constructor & Destructor Documentation

◆ btree_set() [1/5]

btree_set ( const allocator_type alloc = allocator_type())
inlineexplicit

Default constructor initializing an empty B+ tree with the standard key comparison function.

Definition at line 177 of file btree_set.hpp.

◆ btree_set() [2/5]

btree_set ( const key_compare kcf,
const allocator_type alloc = allocator_type() 
)
inlineexplicit

Constructor initializing an empty B+ tree with a special key comparison object.

Definition at line 183 of file btree_set.hpp.

◆ btree_set() [3/5]

btree_set ( InputIterator  first,
InputIterator  last,
const allocator_type alloc = allocator_type() 
)
inline

Constructor initializing a B+ tree with the range [first,last)

Definition at line 190 of file btree_set.hpp.

◆ btree_set() [4/5]

btree_set ( InputIterator  first,
InputIterator  last,
const key_compare kcf,
const allocator_type alloc = allocator_type() 
)
inline

Constructor initializing a B+ tree with the range [first,last) and a special key comparison object.

Definition at line 199 of file btree_set.hpp.

◆ ~btree_set()

~btree_set ( )
inline

Frees up all used B+ tree memory pages.

Definition at line 206 of file btree_set.hpp.

◆ btree_set() [5/5]

btree_set ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other)
inline

Copy constructor.

The newly initialized B+ tree object will contain a copy of all keys.

Definition at line 453 of file btree_set.hpp.

Member Function Documentation

◆ begin() [1/2]

iterator begin ( )
inline

Constructs a read/data-write iterator that points to the first slot in the first leaf of the B+ tree.

Definition at line 261 of file btree_set.hpp.

◆ begin() [2/2]

const_iterator begin ( ) const
inline

Constructs a read-only constant iterator that points to the first slot in the first leaf of the B+ tree.

Definition at line 273 of file btree_set.hpp.

◆ bulk_load()

void bulk_load ( Iterator  first,
Iterator  last 
)
inline

Bulk load a sorted range [first,last).

Loads items into leaves and constructs a B-tree above them. The tree must be empty when calling this function.

Definition at line 491 of file btree_set.hpp.

◆ clear()

void clear ( )
inline

Frees all keys and all nodes of the tree.

Definition at line 249 of file btree_set.hpp.

◆ count()

size_type count ( const key_type key) const
inline

Tries to locate a key in the B+ tree and returns the number of identical key entries found.

As this is a unique set, count() returns either 0 or

Definition at line 361 of file btree_set.hpp.

◆ empty()

bool empty ( ) const
inline

Returns true if there is at least one key in the B+ tree.

Definition at line 319 of file btree_set.hpp.

◆ end() [1/2]

iterator end ( )
inline

Constructs a read/data-write iterator that points to the first invalid slot in the last leaf of the B+ tree.

Definition at line 267 of file btree_set.hpp.

◆ end() [2/2]

const_iterator end ( ) const
inline

Constructs a read-only constant iterator that points to the first invalid slot in the last leaf of the B+ tree.

Definition at line 279 of file btree_set.hpp.

◆ equal_range() [1/2]

std::pair<iterator, iterator> equal_range ( const key_type key)
inline

Searches the B+ tree and returns both lower_bound() and upper_bound().

Definition at line 390 of file btree_set.hpp.

◆ equal_range() [2/2]

std::pair<const_iterator, const_iterator> equal_range ( const key_type key) const
inline

Searches the B+ tree and returns both lower_bound() and upper_bound().

Definition at line 395 of file btree_set.hpp.

◆ erase() [1/2]

size_type erase ( const key_type key)
inline

Erases all the key/data pairs associated with the given key.

Definition at line 508 of file btree_set.hpp.

◆ erase() [2/2]

void erase ( iterator  iter)
inline

Erase the key/data pair referenced by the iterator.

Definition at line 513 of file btree_set.hpp.

◆ erase_one()

bool erase_one ( const key_type key)
inline

Erases the key from the set.

As this is a unique set, there is no difference to erase().

Definition at line 503 of file btree_set.hpp.

◆ exists()

bool exists ( const key_type key) const
inline

Non-STL function checking whether a key is in the B+ tree.

The same as (find(k) != end()) or (count() != 0).

Definition at line 342 of file btree_set.hpp.

◆ find() [1/2]

iterator find ( const key_type key)
inline

Tries to locate a key in the B+ tree and returns an iterator to the key slot if found.

If unsuccessful it returns end().

Definition at line 348 of file btree_set.hpp.

◆ find() [2/2]

const_iterator find ( const key_type key) const
inline

Tries to locate a key in the B+ tree and returns an constant iterator to the key slot if found.

If unsuccessful it returns end().

Definition at line 354 of file btree_set.hpp.

◆ get_allocator()

allocator_type get_allocator ( ) const
inline

Return the base node allocator provided during construction.

Definition at line 238 of file btree_set.hpp.

◆ get_stats()

const tree_stats& get_stats ( ) const
inline

Return a const reference to the current statistics.

Definition at line 330 of file btree_set.hpp.

◆ insert() [1/3]

std::pair<iterator, bool> insert ( const key_type x)
inline

Attempt to insert a key into the B+ tree.

The insert will fail if it is already present.

Definition at line 465 of file btree_set.hpp.

◆ insert() [2/3]

void insert ( InputIterator  first,
InputIterator  last 
)
inline

Attempt to insert the range [first,last) of iterators dereferencing to key_type into the B+ tree.

Each key/data pair is inserted individually.

Definition at line 478 of file btree_set.hpp.

◆ insert() [3/3]

iterator insert ( iterator  hint,
const key_type x 
)
inline

Attempt to insert a key into the B+ tree.

The iterator hint is currently ignored by the B+ tree insertion routine.

Definition at line 471 of file btree_set.hpp.

◆ key_comp()

key_compare key_comp ( ) const
inline

Constant access to the key comparison object sorting the B+ tree.

Definition at line 221 of file btree_set.hpp.

◆ lower_bound() [1/2]

iterator lower_bound ( const key_type key)
inline

Searches the B+ tree and returns an iterator to the first pair equal to or greater than key, or end() if all keys are smaller.

Definition at line 367 of file btree_set.hpp.

◆ lower_bound() [2/2]

const_iterator lower_bound ( const key_type key) const
inline

Searches the B+ tree and returns a constant iterator to the first pair equal to or greater than key, or end() if all keys are smaller.

Definition at line 373 of file btree_set.hpp.

◆ max_size()

size_type max_size ( ) const
inline

Returns the largest possible size of the B+ Tree.

This is just a function required by the STL standard, the B+ Tree can hold more items.

Definition at line 325 of file btree_set.hpp.

◆ operator!=()

bool operator!= ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other) const
inline

Inequality relation. Based on operator==.

Definition at line 413 of file btree_set.hpp.

◆ operator<()

bool operator< ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other) const
inline

Total ordering relation of B+ trees of the same type.

It uses std::lexicographical_compare() for the actual comparison of elements.

Definition at line 419 of file btree_set.hpp.

◆ operator<=()

bool operator<= ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other) const
inline

Less-equal relation. Based on operator<.

Definition at line 429 of file btree_set.hpp.

◆ operator=()

btree_set& operator= ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other)
inline

Assignment operator. All the keys are copied.

Definition at line 445 of file btree_set.hpp.

◆ operator==()

bool operator== ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other) const
inline

Equality relation of B+ trees of the same type.

B+ trees of the same size and equal elements are considered equal.

Definition at line 408 of file btree_set.hpp.

◆ operator>()

bool operator> ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other) const
inline

Greater relation. Based on operator<.

Definition at line 424 of file btree_set.hpp.

◆ operator>=()

bool operator>= ( const btree_set< Key_, Compare_, Traits_, Alloc_ > &  other) const
inline

Greater-equal relation. Based on operator<.

Definition at line 434 of file btree_set.hpp.

◆ rbegin() [1/2]

reverse_iterator rbegin ( )
inline

Constructs a read/data-write reverse iterator that points to the first invalid slot in the last leaf of the B+ tree.

Uses STL magic.

Definition at line 285 of file btree_set.hpp.

◆ rbegin() [2/2]

const_reverse_iterator rbegin ( ) const
inline

Constructs a read-only reverse iterator that points to the first invalid slot in the last leaf of the B+ tree.

Uses STL magic.

Definition at line 297 of file btree_set.hpp.

◆ rend() [1/2]

reverse_iterator rend ( )
inline

Constructs a read/data-write reverse iterator that points to the first slot in the first leaf of the B+ tree.

Uses STL magic.

Definition at line 291 of file btree_set.hpp.

◆ rend() [2/2]

const_reverse_iterator rend ( ) const
inline

Constructs a read-only reverse iterator that points to the first slot in the first leaf of the B+ tree.

Uses STL magic.

Definition at line 303 of file btree_set.hpp.

◆ size()

size_type size ( ) const
inline

Return the number of keys in the B+ tree.

Definition at line 314 of file btree_set.hpp.

◆ swap()

void swap ( btree_set< Key_, Compare_, Traits_, Alloc_ > &  from)
inline

Fast swapping of two identical B+ tree objects.

Definition at line 210 of file btree_set.hpp.

◆ upper_bound() [1/2]

iterator upper_bound ( const key_type key)
inline

Searches the B+ tree and returns an iterator to the first pair greater than key, or end() if all keys are smaller or equal.

Definition at line 379 of file btree_set.hpp.

◆ upper_bound() [2/2]

const_iterator upper_bound ( const key_type key) const
inline

Searches the B+ tree and returns a constant iterator to the first pair greater than key, or end() if all keys are smaller or equal.

Definition at line 385 of file btree_set.hpp.

◆ value_comp()

value_compare value_comp ( ) const
inline

Constant access to a constructed value_type comparison object.

required by the STL

Definition at line 227 of file btree_set.hpp.

◆ verify()

void verify ( ) const
inline

Run a thorough verification of all B+ tree invariants.

The program aborts via TLX_BTREE_ASSERT() if something is wrong.

Definition at line 554 of file btree_set.hpp.

Member Data Documentation

◆ allow_duplicates

const bool allow_duplicates
static

Operational parameter: Allow duplicate keys in the btree.

Definition at line 138 of file btree_set.hpp.

◆ debug

const bool debug
static

Debug parameter: Prints out lots of debug information about how the algorithms change the tree.

Requires the header file to be compiled with TLX_BTREE_DEBUG and the key type must be std::ostream printable.

Definition at line 135 of file btree_set.hpp.

◆ inner_slotmax

const unsigned short inner_slotmax
static

Base B+ tree parameter: The number of key slots in each inner node, this can differ from slots in each leaf.

Definition at line 116 of file btree_set.hpp.

◆ inner_slotmin

const unsigned short inner_slotmin
static

Computed B+ tree parameter: The minimum number of key slots used in an inner node.

If fewer slots are used, the inner node will be merged or slots shifted from it's siblings.

Definition at line 126 of file btree_set.hpp.

◆ leaf_slotmax

const unsigned short leaf_slotmax
static

Base B+ tree parameter: The number of key slots in each leaf.

Definition at line 112 of file btree_set.hpp.

◆ leaf_slotmin

const unsigned short leaf_slotmin
static

Computed B+ tree parameter: The minimum number of key slots used in a leaf.

If fewer slots are used, the leaf will be merged or slots shifted from it's siblings.

Definition at line 121 of file btree_set.hpp.

◆ self_verify

const bool self_verify
static

Debug parameter: Enables expensive and thorough checking of the B+ tree invariants after each insert/erase operation.

Definition at line 130 of file btree_set.hpp.

◆ TLX_BTREE_FRIENDS

TLX_BTREE_FRIENDS

The macro TLX_BTREE_FRIENDS can be used by outside class to access the B+ tree internals.

This was added for wxBTreeDemo to be able to draw the tree.

Definition at line 74 of file btree_set.hpp.

◆ tree_

btree_impl tree_
private

The contained implementation object.

Definition at line 167 of file btree_set.hpp.


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