org.apache.lucene.analysis.miscellaneous
Class LimitTokenCountFilter

java.lang.Object
  org.apache.lucene.util.AttributeSource
      org.apache.lucene.analysis.TokenStream
          org.apache.lucene.analysis.TokenFilter
              org.apache.lucene.analysis.miscellaneous.LimitTokenCountFilter

All Implemented Interfaces:

Closeable

public final class LimitTokenCountFilter
extends TokenFilter

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

By default, this filter ignores any tokens in the wrapped TokenStream once the limit has been reached, which can result in reset() being called prior to incrementToken() returning false. For most TokenStream implementations this should be acceptable, and faster then consuming the full stream. If you are wrapping a TokenStream which requires that the full stream of tokens be exhausted in order to function properly, use the consumeAllTokens option.

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

LimitTokenCountFilter(TokenStream in, int maxTokenCount)
Build a filter that only accepts tokens up to a maximum number.

LimitTokenCountFilter(TokenStream in, int maxTokenCount, boolean consumeAllTokens)
Build an filter that limits the maximum number of tokens per field.

Method Summary

boolean	incrementToken()
void	reset()

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

LimitTokenCountFilter

public LimitTokenCountFilter(TokenStream in,
                             int maxTokenCount)

Build a filter that only accepts tokens up to a maximum number. This filter will not consume any tokens beyond the maxTokenCount limit

See Also:

LimitTokenCountFilter(TokenStream,int,boolean)

LimitTokenCountFilter

public LimitTokenCountFilter(TokenStream in,
                             int maxTokenCount,
                             boolean consumeAllTokens)

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

Parameters:

in - the stream to wrap

maxTokenCount - max number of tokens to produce

consumeAllTokens - whether all tokens from the input must be consumed even if maxTokenCount is reached.

Method Detail

incrementToken

public boolean incrementToken()
                       throws IOException

Specified by:

incrementToken in class TokenStream

Throws:

IOException

reset

public void reset()
           throws IOException

Overrides:

reset in class TokenFilter

Throws:

IOException