de.jungblut.datastructure

Class HuffmanTree<VALUE>

java.lang.Object

de.jungblut.datastructure.HuffmanTree<VALUE>

Type Parameters:

VALUE - the value that wants to be encoded.

public final class HuffmanTree<VALUE>
extends Object

Huffman tree coder that takes input from a Multiset and returns huffman codes getHuffmanCodes(). Features generic and object tree representation which uses lots of ram and will be replaced with an array based version soon.

Author:

thomas.jungblut

Constructor Summary

Constructors

Constructor and Description
HuffmanTree()

Method Summary

Modifier and Type	Method and Description
void	addAll(com.google.common.collect.Multiset<VALUE> multiSet) Bulk inserts the given multiset into this huffman tree.
VALUE	decode(de.jungblut.math.sparse.SparseBitVector vector) Decodes a given vector.
int	getCardinality()
Map<VALUE,de.jungblut.math.sparse.SparseBitVector>	getHuffmanCodes() Bulk returns all generated Huffman codes as a bit vector representation.

Methods inherited from class java.lang.Object

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

Constructor Detail

HuffmanTree

public HuffmanTree()

Method Detail

addAll

public void addAll(com.google.common.collect.Multiset<VALUE> multiSet)

Bulk inserts the given multiset into this huffman tree.

Parameters:

multiSet - a multiset that contains value mappings to their frequency.

getHuffmanCodes

public Map<VALUE,de.jungblut.math.sparse.SparseBitVector> getHuffmanCodes()

Bulk returns all generated Huffman codes as a bit vector representation.

Returns:

the mapping between value and its binary code.

decode

public VALUE decode(de.jungblut.math.sparse.SparseBitVector vector)

Decodes a given vector.

Parameters:

vector - the bit vector to decode.

Returns:

null if the code doesn't exist, or the value if it does.

getCardinality

public int getCardinality()

Returns:

the number of bits needed to encode every item in this tree uniquely.