C# Class Lucene.Net.Util.BytesRefHash

BytesRefHash is a special purpose hash-map like data-structure optimized for BytesRef instances. BytesRefHash maintains mappings of byte arrays to ids (Map<BytesRef,int>) storing the hashed bytes efficiently in continuous storage. The mapping to the id is encapsulated inside BytesRefHash and is guaranteed to be increased for each added BytesRef.

Note: The maximum capacity BytesRef instance passed to #add(BytesRef) must not be longer than ByteBlockPool#BYTE_BLOCK_SIZE-2. The internal storage is limited to 2GB total byte storage.

@lucene.internal

Show file Open project: apache/lucenenet Class Usage Examples

Public Methods

Method	Description
Add ( BytesRef bytes ) : int	Adds a new BytesRef
AddByPoolOffset ( int offset ) : int	Adds a "arbitrary" int offset instead of a BytesRef term. this is used in the indexer to hold the hash for term vectors, because they do not redundantly store the byte[] term directly and instead reference the byte[] term already stored by the postings BytesRefHash. See add(int textStart) in TermsHashPerField.
ByteStart ( int bytesID ) : int	Returns the bytesStart offset into the internally used ByteBlockPool for the given bytesID
BytesRefHash ( ) : System	Creates a new BytesRefHash with a ByteBlockPool using a DirectAllocator.
BytesRefHash ( Lucene.Net.Util.ByteBlockPool pool ) : System	Creates a new BytesRefHash
BytesRefHash ( Lucene.Net.Util.ByteBlockPool pool, int capacity, BytesStartArray bytesStartArray ) : System	Creates a new BytesRefHash
Clear ( ) : void
Clear ( bool resetPool ) : void	Clears the BytesRef which maps to the given BytesRef
Close ( ) : void	Closes the BytesRefHash and releases all internally used memory
Compact ( ) : int[]	Returns the ids array in arbitrary order. Valid ids start at offset of 0 and end at a limit of #size() - 1 Note: this is a destructive operation. #clear() must be called in order to reuse this BytesRefHash instance.
Find ( BytesRef bytes ) : int	Returns the id of the given BytesRef.
Get ( int bytesID, BytesRef @ref ) : BytesRef	Populates and returns a BytesRef with the bytes for the given bytesID. Note: the given bytesID must be a positive integer less than the current size (#size())
Reinit ( ) : void	reinitializes the BytesRefHash after a previous #clear() call. If #clear() has not been called previously this method has no effect.
Size ( ) : int	Returns the number of BytesRef values in this BytesRefHash.
Sort ( IComparer comp ) : int[]	Returns the values array sorted by the referenced byte values. Note: this is a destructive operation. #clear() must be called in order to reuse this BytesRefHash instance.

Private Methods

Method	Description
DoHash ( byte bytes, int offset, int length ) : int
Equals ( int id, BytesRef b ) : bool
FindHash ( BytesRef bytes ) : int
Rehash ( int newSize, bool hashOnData ) : void	Called when hash is too small (> 50% occupied) or too large (< 20% occupied).
Shrink ( int targetSize ) : bool

Method Details

Add() public method

Adds a new BytesRef

/// if the given bytes are > 2 + ///

public Add ( BytesRef bytes ) : int
bytes	BytesRef	/// the bytes to hash
return	int

AddByPoolOffset() public method

Adds a "arbitrary" int offset instead of a BytesRef term. this is used in the indexer to hold the hash for term vectors, because they do not redundantly store the byte[] term directly and instead reference the byte[] term already stored by the postings BytesRefHash. See add(int textStart) in TermsHashPerField.

public AddByPoolOffset ( int offset ) : int
offset	int
return	int

ByteStart() public method

Returns the bytesStart offset into the internally used ByteBlockPool for the given bytesID

public ByteStart ( int bytesID ) : int
bytesID	int	/// the id to look up
return	int

BytesRefHash() public method

Creates a new BytesRefHash with a ByteBlockPool using a DirectAllocator.

public BytesRefHash ( ) : System
return	System

BytesRefHash() public method

Creates a new BytesRefHash

public BytesRefHash ( Lucene.Net.Util.ByteBlockPool pool ) : System
pool	Lucene.Net.Util.ByteBlockPool
return	System

BytesRefHash() public method

Creates a new BytesRefHash

public BytesRefHash ( Lucene.Net.Util.ByteBlockPool pool, int capacity, BytesStartArray bytesStartArray ) : System
pool	Lucene.Net.Util.ByteBlockPool
capacity	int
bytesStartArray	BytesStartArray
return	System

Clear() public method

public Clear ( ) : void
return	void

Clear() public method

Clears the BytesRef which maps to the given BytesRef

public Clear ( bool resetPool ) : void
resetPool	bool
return	void

Close() public method

Closes the BytesRefHash and releases all internally used memory

public Close ( ) : void
return	void

Compact() public method

Returns the ids array in arbitrary order. Valid ids start at offset of 0 and end at a limit of #size() - 1

Note: this is a destructive operation. #clear() must be called in order to reuse this BytesRefHash instance.

public Compact ( ) : int[]
return	int[]

Find() public method

Returns the id of the given BytesRef.

public Find ( BytesRef bytes ) : int
bytes	BytesRef	/// the bytes to look for ///
return	int

Get() public method

Populates and returns a BytesRef with the bytes for the given bytesID.

Note: the given bytesID must be a positive integer less than the current size (#size())

public Get ( int bytesID, BytesRef @ref ) : BytesRef
bytesID	int	/// the id
@ref	BytesRef
return	BytesRef

Reinit() public method

reinitializes the BytesRefHash after a previous #clear() call. If #clear() has not been called previously this method has no effect.

public Reinit ( ) : void
return	void

Size() public method

Returns the number of BytesRef values in this BytesRefHash.

public Size ( ) : int
return	int

Sort() public method

Returns the values array sorted by the referenced byte values.

Note: this is a destructive operation. #clear() must be called in order to reuse this BytesRefHash instance.

public Sort ( IComparer comp ) : int[]
comp	IComparer	/// the used for sorting
return	int[]