Class AnalysisOffsetStrategy.MultiValueTokenStream
- java.lang.Object
-
- org.apache.lucene.util.AttributeSource
-
- org.apache.lucene.analysis.TokenStream
-
- org.apache.lucene.analysis.TokenFilter
-
- org.apache.lucene.search.uhighlight.AnalysisOffsetStrategy.MultiValueTokenStream
-
- All Implemented Interfaces:
java.io.Closeable
,java.lang.AutoCloseable
- Enclosing class:
- AnalysisOffsetStrategy
private static final class AnalysisOffsetStrategy.MultiValueTokenStream extends TokenFilter
Wraps anAnalyzer
and string text that represents multiple values delimited by a specified character. This exposes a TokenStream that matches what would get indexed considering theAnalyzer.getPositionIncrementGap(String)
. Currently this assumesAnalyzer.getOffsetGap(String)
is 1; an exception will be thrown if it isn't.
It would be more orthogonal for this to be an Analyzer since we're wrapping an Analyzer but doing so seems like more work. The underlying components see a Reader not a String -- and the String is easy to split up without redundant buffering.
-
-
Nested Class Summary
-
Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource
AttributeSource.State
-
-
Field Summary
Fields Modifier and Type Field Description private java.lang.String
content
private int
endValIdx
private java.lang.String
fieldName
private Analyzer
indexAnalyzer
private OffsetAttribute
offsetAtt
private PositionIncrementAttribute
posIncAtt
private int
remainingPosInc
private char
splitChar
private int
startValIdx
-
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 Modifier Constructor Description private
MultiValueTokenStream(TokenStream subTokenStream, java.lang.String fieldName, Analyzer indexAnalyzer, java.lang.String content, char splitChar, int splitCharIdx)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
end()
This method is called by the consumer after the last token has been consumed, afterTokenStream.incrementToken()
returnedfalse
(using the newTokenStream
API).boolean
incrementToken()
Consumers (i.e.,IndexWriter
) use this method to advance the stream to the next token.void
reset()
This method is called by a consumer before it begins consumption usingTokenStream.incrementToken()
.-
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, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString
-
-
-
-
Field Detail
-
fieldName
private final java.lang.String fieldName
-
indexAnalyzer
private final Analyzer indexAnalyzer
-
content
private final java.lang.String content
-
splitChar
private final char splitChar
-
posIncAtt
private final PositionIncrementAttribute posIncAtt
-
offsetAtt
private final OffsetAttribute offsetAtt
-
startValIdx
private int startValIdx
-
endValIdx
private int endValIdx
-
remainingPosInc
private int remainingPosInc
-
-
Constructor Detail
-
MultiValueTokenStream
private MultiValueTokenStream(TokenStream subTokenStream, java.lang.String fieldName, Analyzer indexAnalyzer, java.lang.String content, char splitChar, int splitCharIdx)
-
-
Method Detail
-
reset
public void reset() throws java.io.IOException
Description copied from class:TokenFilter
This method is called by a consumer before it begins consumption usingTokenStream.incrementToken()
.Resets this stream to a clean state. Stateful implementations must implement this method so that they can be reused, just as if they had been created fresh.
If you override this method, always call
super.reset()
, otherwise some internal state will not be correctly reset (e.g.,Tokenizer
will throwIllegalStateException
on further usage).NOTE: The default implementation chains the call to the input TokenStream, so be sure to call
super.reset()
when overriding this method.- Overrides:
reset
in classTokenFilter
- Throws:
java.io.IOException
-
incrementToken
public boolean incrementToken() throws java.io.IOException
Description copied from class:TokenStream
Consumers (i.e.,IndexWriter
) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriateAttributeImpl
s with the attributes of the next token.The producer must make no assumptions about the attributes after the method has been returned: the caller may arbitrarily change it. If the producer needs to preserve the state for subsequent calls, it can use
AttributeSource.captureState()
to create a copy of the current attribute state.This method is called for every token of a document, so an efficient implementation is crucial for good performance. To avoid calls to
AttributeSource.addAttribute(Class)
andAttributeSource.getAttribute(Class)
, references to allAttributeImpl
s that this stream uses should be retrieved during instantiation.To ensure that filters and consumers know which attributes are available, the attributes must be added during instantiation. Filters and consumers are not required to check for availability of attributes in
TokenStream.incrementToken()
.- Specified by:
incrementToken
in classTokenStream
- Returns:
- false for end of stream; true otherwise
- Throws:
java.io.IOException
-
end
public void end() throws java.io.IOException
Description copied from class:TokenFilter
This method is called by the consumer after the last token has been consumed, afterTokenStream.incrementToken()
returnedfalse
(using the newTokenStream
API). Streams implementing the old API should upgrade to use this feature.This method can be used to perform any end-of-stream operations, such as setting the final offset of a stream. The final offset of a stream might differ from the offset of the last token eg in case one or more whitespaces followed after the last token, but a WhitespaceTokenizer was used.
Additionally any skipped positions (such as those removed by a stopfilter) can be applied to the position increment, or any adjustment of other attributes where the end-of-stream value may be important.
If you override this method, always call
super.end()
.NOTE: The default implementation chains the call to the input TokenStream, so be sure to call
super.end()
first when overriding this method.- Overrides:
end
in classTokenFilter
- Throws:
java.io.IOException
- If an I/O error occurs
-
-