org.apache.lucene.analysis.hunspell
Class HunspellStemFilter

java.lang.Object
  org.apache.lucene.util.AttributeSource
      org.apache.lucene.analysis.TokenStream
          org.apache.lucene.analysis.TokenFilter
              org.apache.lucene.analysis.hunspell.HunspellStemFilter

All Implemented Interfaces:

Closeable

public final class HunspellStemFilter
extends TokenFilter

TokenFilter that uses hunspell affix rules and words to stem tokens. Since hunspell supports a word having multiple stems, this filter can emit multiple tokens for each consumed token

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource

AttributeSource.AttributeFactory, AttributeSource.State

Field Summary

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

input

Constructor Summary

HunspellStemFilter(TokenStream input, HunspellDictionary dictionary)
Creates a new HunspellStemFilter that will stem tokens from the given TokenStream using affix rules in the provided HunspellDictionary

HunspellStemFilter(TokenStream input, HunspellDictionary dictionary, boolean dedup)
Creates a new HunspellStemFilter that will stem tokens from the given TokenStream using affix rules in the provided HunspellDictionary

Method Summary

boolean	incrementToken() Consumers (i.e., IndexWriter) use this method to advance the stream to the next token.
void	reset() Reset the filter as well as the input TokenStream.

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

close, end

Methods inherited from class org.apache.lucene.util.AttributeSource

addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, restoreState, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

HunspellStemFilter

public HunspellStemFilter(TokenStream input,
                          HunspellDictionary dictionary)

Creates a new HunspellStemFilter that will stem tokens from the given TokenStream using affix rules in the provided HunspellDictionary

Parameters:

input - TokenStream whose tokens will be stemmed

dictionary - HunspellDictionary containing the affix rules and words that will be used to stem the tokens

HunspellStemFilter

public HunspellStemFilter(TokenStream input,
                          HunspellDictionary dictionary,
                          boolean dedup)

Creates a new HunspellStemFilter that will stem tokens from the given TokenStream using affix rules in the provided HunspellDictionary

Parameters:

input - TokenStream whose tokens will be stemmed

dictionary - HunspellDictionary containing the affix rules and words that will be used to stem the tokens

dedup - true if only unique terms should be output.

Method Detail

incrementToken

public boolean incrementToken()
                       throws IOException

Consumers (i.e., IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate AttributeImpls with the attributes of the next token.

The producer must make no assumptions about the attributes after the method has been returned: the caller may arbitrarily change it. If the producer needs to preserve the state for subsequent calls, it can use AttributeSource.captureState() to create a copy of the current attribute state.

This method is called for every token of a document, so an efficient implementation is crucial for good performance. To avoid calls to AttributeSource.addAttribute(Class) and AttributeSource.getAttribute(Class), references to all AttributeImpls that this stream uses should be retrieved during instantiation.

To ensure that filters and consumers know which attributes are available, the attributes must be added during instantiation. Filters and consumers are not required to check for availability of attributes in TokenStream.incrementToken().

Specified by:

incrementToken in class TokenStream

Returns:

false for end of stream; true otherwise

Throws:

IOException

reset

public void reset()
           throws IOException

Reset the filter as well as the input TokenStream.

Overrides:

reset in class TokenFilter

Throws:

IOException