Package it.unimi.dsi.sux4j.mph.codec

Class Codec.Huffman.Coder

java.lang.Object

it.unimi.dsi.sux4j.mph.codec.Codec.Huffman.Coder

All Implemented Interfaces:

Codec.Coder

Enclosing class:

Codec.Huffman

public static final class Codec.Huffman.Coder
extends java.lang.Object
implements Codec.Coder

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Codec.Huffman.Coder.Decoder

Constructor Summary

Constructors

Constructor	Description
Coder(long[] codeWord, int[] codewordLength, long[] symbol, it.unimi.dsi.fastutil.longs.Long2IntMap symbol2Rank, int escapedSymbolLength)

Method Summary

Modifier and Type	Method	Description
int	codewordLength(long symbol)	Returns the length of the codeword associated with the given symbol.
long	encode(long symbol)	Returns the codeword associated with a symbol, or −1 if the provided symbol should be escaped.
long	escape()	Returns the escape codeword, if it exists.
int	escapedSymbolLength()	Returns the length in bit of an escaped symbol, or zero if there are no escaped symbols.
Codec.Huffman.Coder.Decoder	getDecoder()	Return a decoder associated with this coder.
int	maxCodewordLength()	Returns the maximum length of a codeword (including escaped symbols).

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Coder

public Coder(long[] codeWord,
             int[] codewordLength,
             long[] symbol,
             it.unimi.dsi.fastutil.longs.Long2IntMap symbol2Rank,
             int escapedSymbolLength)

Method Detail

encode

public long encode(long symbol)

Description copied from interface: Codec.Coder

Returns the codeword associated with a symbol, or −1 if the provided symbol should be escaped.

If a symbol needs to be escaped, it must be encoded using the escape codeword followed by the symbol written in a field of Codec.Coder.escapedSymbolLength() bits.

Specified by:

encode in interface Codec.Coder

Parameters:

symbol - a symbol.

Returns:

the associated codeword.

codewordLength

public int codewordLength(long symbol)

Description copied from interface: Codec.Coder

Returns the length of the codeword associated with the given symbol.

For escaped symbols, the returned values is the length of the escape codeword plus Codec.Coder.escapedSymbolLength().

Specified by:

codewordLength in interface Codec.Coder

Parameters:

symbol - a symbol provided at construction time.

Returns:

the length of the codeword associated with the given symbol.

maxCodewordLength

public int maxCodewordLength()

Description copied from interface: Codec.Coder

Returns the maximum length of a codeword (including escaped symbols).

Specified by:

maxCodewordLength in interface Codec.Coder

Returns:

the maximum length of a codeword (including escaped symbols).

escape

public long escape()

Description copied from interface: Codec.Coder

Returns the escape codeword, if it exists.

Note that the length of the escape codeword can be recovered by subtracting from the length of the codeword of an escaped symbol the length of an escaped symbol.

Specified by:

escape in interface Codec.Coder

Returns:

the escape codeword, if it exists.

escapedSymbolLength

public int escapedSymbolLength()

Description copied from interface: Codec.Coder

Returns the length in bit of an escaped symbol, or zero if there are no escaped symbols.

Specified by:

escapedSymbolLength in interface Codec.Coder

Returns:

the length in bit of an escaped symbol, or zero if there are no escaped symbols.

getDecoder

public Codec.Huffman.Coder.Decoder getDecoder()

Description copied from interface: Codec.Coder

Return a decoder associated with this coder.

Specified by:

getDecoder in interface Codec.Coder

Returns:

a decoder associated with this coder.