org.apache.lucene.analysis
Class LimitTokenCountAnalyzer

java.lang.Object
  org.apache.lucene.analysis.Analyzer
      org.apache.lucene.analysis.LimitTokenCountAnalyzer

All Implemented Interfaces:

Closeable

public final class LimitTokenCountAnalyzer
extends Analyzer

This Analyzer limits the number of tokens while indexing. It is a replacement for the maximum field length setting inside IndexWriter.

Constructor Summary

LimitTokenCountAnalyzer(Analyzer delegate, int maxTokenCount)
Build an analyzer that limits the maximum number of tokens per field.

Method Summary

int	getOffsetGap(Fieldable field) Just like Analyzer.getPositionIncrementGap(java.lang.String), except for Token offsets instead.
int	getPositionIncrementGap(String fieldName) Invoked before indexing a Fieldable instance if terms have already been added to that field.
TokenStream	reusableTokenStream(String fieldName, Reader reader) Creates a TokenStream that is allowed to be re-used from the previous time that the same thread called this method.
TokenStream	tokenStream(String fieldName, Reader reader) Creates a TokenStream which tokenizes all the text in the provided Reader.
String	toString()

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

close, getPreviousTokenStream, setPreviousTokenStream

Methods inherited from class java.lang.Object

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

Constructor Detail

LimitTokenCountAnalyzer

public LimitTokenCountAnalyzer(Analyzer delegate,
                               int maxTokenCount)

Build an analyzer that limits the maximum number of tokens per field.

Method Detail

tokenStream

public TokenStream tokenStream(String fieldName,
                               Reader reader)

Description copied from class: Analyzer

Creates a TokenStream which tokenizes all the text in the provided Reader. Must be able to handle null field name for backward compatibility.

Specified by:

tokenStream in class Analyzer

reusableTokenStream

public TokenStream reusableTokenStream(String fieldName,
                                       Reader reader)
                                throws IOException

Description copied from class: Analyzer

Creates a TokenStream that is allowed to be re-used from the previous time that the same thread called this method. Callers that do not need to use more than one TokenStream at the same time from this analyzer should use this method for better performance.

Overrides:

reusableTokenStream in class Analyzer

Throws:

IOException

getPositionIncrementGap

public int getPositionIncrementGap(String fieldName)

Description copied from class: Analyzer

Invoked before indexing a Fieldable instance if terms have already been added to that field. This allows custom analyzers to place an automatic position increment gap between Fieldable instances using the same field name. The default value position increment gap is 0. With a 0 position increment gap and the typical default token position increment of 1, all terms in a field, including across Fieldable instances, are in successive positions, allowing exact PhraseQuery matches, for instance, across Fieldable instance boundaries.

Overrides:

getPositionIncrementGap in class Analyzer

Parameters:

fieldName - Fieldable name being indexed.

Returns:

position increment gap, added to the next token emitted from Analyzer.tokenStream(String,Reader)

getOffsetGap

public int getOffsetGap(Fieldable field)

Description copied from class: Analyzer

Just like Analyzer.getPositionIncrementGap(java.lang.String), except for Token offsets instead. By default this returns 1 for tokenized fields and, as if the fields were joined with an extra space character, and 0 for un-tokenized fields. This method is only called if the field produced at least one token for indexing.

Overrides:

getOffsetGap in class Analyzer

Parameters:

field - the field just indexed

Returns:

offset gap, added to the next token emitted from Analyzer.tokenStream(String,Reader)

toString

public String toString()

Overrides:

toString in class Object