org.apache.lucene.analysis.ngram
Class NGramTokenizer

java.lang.Object
  org.apache.lucene.util.AttributeSource
      org.apache.lucene.analysis.TokenStream
          org.apache.lucene.analysis.Tokenizer
              org.apache.lucene.analysis.ngram.NGramTokenizer

All Implemented Interfaces:

Closeable

public final class NGramTokenizer
extends org.apache.lucene.analysis.Tokenizer

Tokenizes the input into n-grams of the given size(s).

Nested Class Summary

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

org.apache.lucene.util.AttributeSource.AttributeFactory, org.apache.lucene.util.AttributeSource.State

Field Summary

static int	DEFAULT_MAX_NGRAM_SIZE
static int	DEFAULT_MIN_NGRAM_SIZE

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

input

Constructor Summary

NGramTokenizer(org.apache.lucene.util.AttributeSource.AttributeFactory factory, Reader input, int minGram, int maxGram)
Creates NGramTokenizer with given min and max n-grams.

NGramTokenizer(org.apache.lucene.util.AttributeSource source, Reader input, int minGram, int maxGram)
Creates NGramTokenizer with given min and max n-grams.

NGramTokenizer(Reader input)
Creates NGramTokenizer with default min and max n-grams.

NGramTokenizer(Reader input, int minGram, int maxGram)
Creates NGramTokenizer with given min and max n-grams.

Method Summary

void	end()
boolean	incrementToken() Returns the next token in the stream, or null at EOS.
void	reset()
void	reset(Reader input)

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

close, correctOffset

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

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

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MIN_NGRAM_SIZE

public static final int DEFAULT_MIN_NGRAM_SIZE

See Also:

Constant Field Values

DEFAULT_MAX_NGRAM_SIZE

public static final int DEFAULT_MAX_NGRAM_SIZE

See Also:

Constant Field Values

Constructor Detail

NGramTokenizer

public NGramTokenizer(Reader input,
                      int minGram,
                      int maxGram)

Creates NGramTokenizer with given min and max n-grams.

Parameters:

input - Reader holding the input to be tokenized

minGram - the smallest n-gram to generate

maxGram - the largest n-gram to generate

NGramTokenizer

public NGramTokenizer(org.apache.lucene.util.AttributeSource source,
                      Reader input,
                      int minGram,
                      int maxGram)

Creates NGramTokenizer with given min and max n-grams.

Parameters:

source - AttributeSource to use

input - Reader holding the input to be tokenized

minGram - the smallest n-gram to generate

maxGram - the largest n-gram to generate

NGramTokenizer

public NGramTokenizer(org.apache.lucene.util.AttributeSource.AttributeFactory factory,
                      Reader input,
                      int minGram,
                      int maxGram)

Creates NGramTokenizer with given min and max n-grams.

Parameters:

factory - AttributeSource.AttributeFactory to use

input - Reader holding the input to be tokenized

minGram - the smallest n-gram to generate

maxGram - the largest n-gram to generate

NGramTokenizer

public NGramTokenizer(Reader input)

Creates NGramTokenizer with default min and max n-grams.

Parameters:

input - Reader holding the input to be tokenized

Method Detail

incrementToken

public final boolean incrementToken()
                             throws IOException

Returns the next token in the stream, or null at EOS.

Specified by:

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

Throws:

IOException

end

public final void end()

Overrides:

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

reset

public void reset(Reader input)
           throws IOException

Overrides:

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

Throws:

IOException

reset

public void reset()
           throws IOException

Overrides:

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

Throws:

IOException