com.s24.search.solr.analyzers

Class AnalyzingSentenceTokenizer

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.Tokenizer

com.s24.search.solr.analyzers.AnalyzingSentenceTokenizer

All Implemented Interfaces:

Closeable, AutoCloseable

public class AnalyzingSentenceTokenizer
extends org.apache.lucene.analysis.Tokenizer

Tokenizer which splits the input into sentences and emits only those sentences that do not contain too many stopwords. Sentences that contain many commas are split into their comma-separated parts and analyzed per part. If the input contains only a single sentence, it is always emitted.

Author:

Shopping24 GmbH

Nested Class Summary

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

org.apache.lucene.util.AttributeSource.State

Field Summary

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

input

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

DEFAULT_TOKEN_ATTRIBUTE_FACTORY

Constructor Summary

Constructors

Constructor and Description
AnalyzingSentenceTokenizer(org.apache.lucene.util.AttributeFactory factory, boolean removeBadSentences, org.apache.lucene.analysis.CharArraySet stopWords, float commaWordThreshold, float maxStopwordRatio, int minSentenceLength) Construct a token stream processing the given input using the given AttributeFactory.

Method Summary

Modifier and Type	Method and Description
void	end() Sets the final offset, does not reset internal state.
boolean	incrementToken()
protected boolean	incrementTokenInternal()
void	reset() Method is called after the input has been set.

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

close, correctOffset, setReader

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

AnalyzingSentenceTokenizer

public AnalyzingSentenceTokenizer(org.apache.lucene.util.AttributeFactory factory,
                                  boolean removeBadSentences,
                                  org.apache.lucene.analysis.CharArraySet stopWords,
                                  float commaWordThreshold,
                                  float maxStopwordRatio,
                                  int minSentenceLength)

Construct a token stream processing the given input using the given AttributeFactory.

Parameters:

factory - the factory.

removeBadSentences - if true, sentences with too many stopwords are filtered out.

stopWords - the stopwords.

commaWordThreshold - the threshold that defines the "comma density" that, if exceeded, causes a sentence to be split into sub-sentences that are analyzed individually.

maxStopwordRatio - if the ratio of stopwords exceeds this threshold, the sentence is filtered out.

minSentenceLength - a sentence must contain at least this many words, otherwise it is not analyzed and always emitted.

Method Detail

end

public void end()
         throws IOException

Sets the final offset, does not reset internal state.

Overrides:

end in class org.apache.lucene.analysis.TokenStream

Throws:

IOException

reset

public void reset()
           throws IOException

Method is called after the input has been set. This should reset all internal state and adjust to the new input.

Overrides:

reset in class org.apache.lucene.analysis.Tokenizer

Throws:

IOException

incrementToken

public final boolean incrementToken()
                             throws IOException

Specified by:

incrementToken in class org.apache.lucene.analysis.TokenStream

Returns:

true to indicate to the caller to read the current attribute state and false to indicate the end of the token stream.

Throws:

IOException

incrementTokenInternal

protected boolean incrementTokenInternal()
                                  throws IOException

Returns:

true if the current attribute state should be emitted

Throws:

IOException