Package org.apache.lucene.analysis.miscellaneous

Class FingerprintFilter

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.analysis.miscellaneous.FingerprintFilter

All Implemented Interfaces:

Closeable, AutoCloseable, Unwrappable<TokenStream>

public class FingerprintFilter
extends TokenFilter

Filter outputs a single token which is a concatenation of the sorted and de-duplicated set of input tokens. This can be useful for clustering/linking use cases.

Nested Class Summary

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

AttributeSource.State

Field Summary

Fields

Modifier and Type	Field	Description
static int	DEFAULT_MAX_OUTPUT_TOKEN_SIZE
static char	DEFAULT_SEPARATOR

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

input

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

DEFAULT_TOKEN_ATTRIBUTE_FACTORY

Constructor Summary

Constructors

Constructor	Description
FingerprintFilter(TokenStream input)	Create a new FingerprintFilter with default settings
FingerprintFilter(TokenStream input, int maxOutputTokenSize, char separator)	Create a new FingerprintFilter with control over all settings

Method Summary

Modifier and Type	Method	Description
void	end()
boolean	incrementToken()
void	reset()

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

close, unwrap

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

Field Detail

DEFAULT_MAX_OUTPUT_TOKEN_SIZE

public static final int DEFAULT_MAX_OUTPUT_TOKEN_SIZE

See Also:

Constant Field Values

DEFAULT_SEPARATOR

public static final char DEFAULT_SEPARATOR

See Also:

Constant Field Values

Constructor Detail

FingerprintFilter

public FingerprintFilter(TokenStream input)

Create a new FingerprintFilter with default settings

FingerprintFilter

public FingerprintFilter(TokenStream input,
                         int maxOutputTokenSize,
                         char separator)

Create a new FingerprintFilter with control over all settings

Parameters:

input - the source of tokens to be summarized into a single token

maxOutputTokenSize - the maximum length of the summarized output token. If exceeded, no output token is emitted

separator - the character used to separate tokens combined into the single output token

Method Detail

incrementToken

public final boolean incrementToken()
                             throws IOException

Specified by:

incrementToken in class TokenStream

Throws:

IOException

end

public final void end()
               throws IOException

Overrides:

end in class TokenFilter

Throws:

IOException

reset

public void reset()
           throws IOException

Overrides:

reset in class TokenFilter

Throws:

IOException