org.apache.lucene.analysis.compound

Class DictionaryCompoundWordTokenFilter

java.lang.Object

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.analysis.compound.CompoundWordTokenFilterBase

org.apache.lucene.analysis.compound.DictionaryCompoundWordTokenFilter

public class DictionaryCompoundWordTokenFilter
extends CompoundWordTokenFilterBase

A TokenFilter that decomposes compound words found in many germanic languages "Donaudampfschiff" becomes Donau, dampf, schiff so that you can find "Donaudampfschiff" even when you only enter "schiff". It uses a brute-force algorithm to achieve this.

Field Summary

Fields inherited from class org.apache.lucene.analysis.compound.CompoundWordTokenFilterBase

DEFAULT_MAX_SUBWORD_SIZE, DEFAULT_MIN_SUBWORD_SIZE, DEFAULT_MIN_WORD_SIZE, dictionary, maxSubwordSize, minSubwordSize, minWordSize, onlyLongestMatch, tokens

Fields inherited from class org.apache.lucene.analysis.TokenFilter

input

Constructor Summary

Constructors

Constructor and Description
DictionaryCompoundWordTokenFilter(TokenStream input, Set dictionary)
DictionaryCompoundWordTokenFilter(TokenStream input, Set dictionary, int minWordSize, int minSubwordSize, int maxSubwordSize, boolean onlyLongestMatch)
DictionaryCompoundWordTokenFilter(TokenStream input, String[] dictionary)
DictionaryCompoundWordTokenFilter(TokenStream input, String[] dictionary, int minWordSize, int minSubwordSize, int maxSubwordSize, boolean onlyLongestMatch)

Method Summary

Methods

Modifier and Type	Method and Description
protected void	decomposeInternal(Token token)

Methods inherited from class org.apache.lucene.analysis.compound.CompoundWordTokenFilterBase

addAllLowerCase, createToken, decompose, makeDictionary, makeLowerCaseCopy, next

Methods inherited from class org.apache.lucene.analysis.TokenFilter

close, reset

Methods inherited from class org.apache.lucene.analysis.TokenStream

next

Methods inherited from class java.lang.Object

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

Constructor Detail

DictionaryCompoundWordTokenFilter

public DictionaryCompoundWordTokenFilter(TokenStream input,
                                 String[] dictionary,
                                 int minWordSize,
                                 int minSubwordSize,
                                 int maxSubwordSize,
                                 boolean onlyLongestMatch)

Parameters:

input - the token stream to process

dictionary - the word dictionary to match against

minWordSize - only words longer than this get processed

minSubwordSize - only subwords longer than this get to the output stream

maxSubwordSize - only subwords shorter than this get to the output stream

onlyLongestMatch - Add only the longest matching subword to the stream

DictionaryCompoundWordTokenFilter

public DictionaryCompoundWordTokenFilter(TokenStream input,
                                 String[] dictionary)

Parameters:

input - the token stream to process

dictionary - the word dictionary to match against

DictionaryCompoundWordTokenFilter

public DictionaryCompoundWordTokenFilter(TokenStream input,
                                 Set dictionary)

Parameters:

input - the token stream to process

dictionary - the word dictionary to match against. If this is a CharArraySet it must have set ignoreCase=false and only contain lower case strings.

DictionaryCompoundWordTokenFilter

public DictionaryCompoundWordTokenFilter(TokenStream input,
                                 Set dictionary,
                                 int minWordSize,
                                 int minSubwordSize,
                                 int maxSubwordSize,
                                 boolean onlyLongestMatch)

Parameters:

input - the token stream to process

dictionary - the word dictionary to match against. If this is a CharArraySet it must have set ignoreCase=false and only contain lower case strings.

minWordSize - only words longer than this get processed

minSubwordSize - only subwords longer than this get to the output stream

maxSubwordSize - only subwords shorter than this get to the output stream

onlyLongestMatch - Add only the longest matching subword to the stream

Method Detail

decomposeInternal

protected void decomposeInternal(Token token)

Specified by:

decomposeInternal in class CompoundWordTokenFilterBase