BTree

BTree class provides a B-Tree implementation for storing key-value pairs.

It supports basic operations like insert, delete, and search.

Constants

BTREE_HEADER_SIZE

private const BTREE_HEADER_SIZE = 12

VERSION_STRING

private const VERSION_STRING = '1.0'

Properties

version

private Version $version

slotSize

private int $slotSize = 16

keySize

private int $keySize = 32

filePath

private string $filePath

file

private mixed $file

rootNode

private Node $rootNode

readOnly

private bool $readOnly

Methods

__construct

Constructs a new BTree instance.

public __construct(string $filePath, bool $readOnly, int $keySize = 32, int $slotSize = 16): void

Initializes the BTree with the specified file path, key size, and slot size. If the BTree file does not exist, it will be created. Loads the root node from the file.

The header will be written to the file in the format:

• Major version (2 bytes)
• Minor version (2 bytes)
• Slot size (2 bytes)
• Key size (2 bytes)
• Pointer to the root node (4 bytes)

If the file already exists, it will read the header to determine the BTree's configuration.

Parameters

Parameter	Type	Description
$filePath	string	path to the BTree file
$readOnly	bool	if true, the BTree will be opened in read-only mode; otherwise, it will be opened in read-write mode
$keySize	int	Size of the key in bytes. Default is 32.
$slotSize	int	Size of the slot in bytes. Default is 16.

__destruct

Destructor for the BTree class.

public __destruct(): void

Ensures that the BTree file resource is closed when the object is destroyed.

close

Closes the BTree file resource.

public close(): void

reset

Resets the B-Tree by reloading the root node from the file.

public reset(): bool

set

Sets the value for the specified key in the B-Tree.

public set(string $key, mixed $value): bool

Parameters

Parameter	Type	Description
$key	string	the key to set in the B-Tree
$value	mixed	the value to associate with the key

get

Gets the value for the specified key from the B-Tree.

public get(string $key): mixed

Parameters

Parameter	Type	Description
$key	string	the key to get from the B-Tree

has

public has(string $key): bool

Parameters

Parameter	Type	Description
$key	string

remove

Removes the specified key from the B-Tree.

public remove(string $key): bool

Parameters

Parameter	Type	Description
$key	string	the key to remove from the B-Tree

compact

Compacts the B-Tree file to reduce its size.

public compact(float $fillFactor = 0.5): bool

Parameters

Parameter	Type	Description
$fillFactor	float	the fill factor for compacting the B-Tree, default is 0.5 This is used to determine how full the nodes should be after compaction. * A fill factor of 0.5 means that nodes will be 50% full after compaction. * A fill factor of 0.8 means that nodes will be 80% full after compaction.

count

Returns the total number of elements in the B-tree.

public count(): int

getIterator

Returns a generator that yields all records in the B-Tree.

public getIterator(): void

This method traverses the B-Tree and yields each record's key and value.

Empties the B-Tree by creating a new root node.

public (): bool

toArray

Return the entire B-Tree as an array.

public toArray(): void

verify

Verifies the integrity of the B-Tree.

public verify(): bool

addLeafToTree

Adds a new leaf node to the B-Tree.

private addLeafToTree(array $nodeTree, mixed $file, Node $newLeafNode): void

This method is used internally to add a new leaf node to the B-Tree structure. It checks if the new leaf node is full and adds it to the tree if necessary.

Parameters

Parameter	Type	Description
$nodeTree	array	The current node tree
$file	mixed	The file resource for the B-Tree
$newLeafNode	Node	The new leaf node to be added

propagateNodeTree

Adds a node to the B-Tree.

private propagateNodeTree(array $nodeTree, mixed $file, int $fillCount): void

This method is used internally to add a new node to the B-Tree structure. It checks if the new node is full and propagates it upwards in the tree if necessary.

Parameters

Parameter	Type	Description
$nodeTree	array	The current node tree
$file	mixed	The file resource for the B-Tree
$fillCount	int	The fill count for the nodes

readHeader

Loads the root node from the B-Tree file.

private readHeader(): bool

writeHeader

Writes the header to the B-Tree file.

private writeHeader(mixed $file, ?Node $rootNode): bool

Parameters

Parameter	Type	Description
$file	mixed
$rootNode	Node

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Generated by Hazaar API Doc Generator on Sat, 23 Aug 2025 22:23:42 +0000