org.apache.lucene.analysis.sinks

Class TeeSinkTokenFilter

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.analysis.sinks.TeeSinkTokenFilter

All Implemented Interfaces:

Closeable, AutoCloseable

public final class TeeSinkTokenFilter
extends TokenFilter

This TokenFilter provides the ability to set aside attribute states that have already been analyzed. This is useful in situations where multiple fields share many common analysis steps and then go their separate ways.

It is also useful for doing things like entity extraction or proper noun analysis as part of the analysis workflow and saving off those tokens for use in another field.

 TeeSinkTokenFilter source1 = new TeeSinkTokenFilter(new WhitespaceTokenizer());
 TeeSinkTokenFilter.SinkTokenStream sink1 = source1.newSinkTokenStream();
 TeeSinkTokenFilter.SinkTokenStream sink2 = source1.newSinkTokenStream();

 TokenStream final1 = new LowerCaseFilter(source1);
 TokenStream final2 = new EntityDetect(sink1);
 TokenStream final3 = new URLDetect(sink2);

 d.add(new TextField("f1", final1));
 d.add(new TextField("f2", final2));
 d.add(new TextField("f3", final3));
 

In this example, sink1 and sink2 will both get tokens from source1 after whitespace tokenization, and will further do additional token filtering, e.g. detect entities and URLs.

NOTE: it is important, that tees are consumed before sinks, therefore you should add them to the document before the sinks. In the above example, f1 is added before the other fields, and so by the time they are processed, it has already been consumed, which is the correct way to index the three streams. If for some reason you cannot ensure that, you should call consumeAllTokens() before adding the sinks to document fields.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TeeSinkTokenFilter.SinkTokenStream TokenStream output from a tee.

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

AttributeSource.State

Field Summary

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 and Description
TeeSinkTokenFilter(TokenStream input)

Method Summary

Methods

Modifier and Type	Method and Description
void	consumeAllTokens() TeeSinkTokenFilter passes all tokens to the added sinks when itself is consumed.
void	end()
boolean	incrementToken()
TokenStream	newSinkTokenStream() Returns a new TeeSinkTokenFilter.SinkTokenStream that receives all tokens consumed by this stream.
void	reset()

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

close

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, removeAllAttributes, restoreState, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

TeeSinkTokenFilter

public TeeSinkTokenFilter(TokenStream input)

Method Detail

newSinkTokenStream

public TokenStream newSinkTokenStream()

Returns a new TeeSinkTokenFilter.SinkTokenStream that receives all tokens consumed by this stream.

consumeAllTokens

public void consumeAllTokens()
                      throws IOException

TeeSinkTokenFilter passes all tokens to the added sinks when itself is consumed. To be sure that all tokens from the input stream are passed to the sinks, you can call this methods. This instance is exhausted after this method returns, but all sinks are instant available.

Throws:

IOException

incrementToken

public 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