public final class ConcatenateGraphFilter extends TokenStream
Modifier and Type | Class and Description |
---|---|
static interface |
ConcatenateGraphFilter.BytesRefBuilderTermAttribute
Attribute providing access to the term builder and UTF-16 conversion
|
static class |
ConcatenateGraphFilter.BytesRefBuilderTermAttributeImpl
Implementation of
ConcatenateGraphFilter.BytesRefBuilderTermAttribute |
private static class |
ConcatenateGraphFilter.EscapingTokenStreamToAutomaton
Just escapes the
SEP_LABEL byte with an extra. |
AttributeSource.State
Modifier and Type | Field and Description |
---|---|
private ConcatenateGraphFilter.BytesRefBuilderTermAttribute |
bytesAtt |
private CharTermAttribute |
charTermAttribute |
static int |
DEFAULT_MAX_GRAPH_EXPANSIONS |
static boolean |
DEFAULT_PRESERVE_POSITION_INCREMENTS |
static boolean |
DEFAULT_PRESERVE_SEP |
private int |
endOffset |
private LimitedFiniteStringsIterator |
finiteStrings |
private TokenStream |
inputTokenStream |
private int |
maxGraphExpansions |
private OffsetAttribute |
offsetAtt |
private PositionIncrementAttribute |
posIncrAtt |
private boolean |
preservePositionIncrements |
private boolean |
preserveSep |
static int |
SEP_LABEL
Represents the separation between tokens, if
preserveSep is true . |
private boolean |
wasReset |
DEFAULT_TOKEN_ATTRIBUTE_FACTORY
Constructor and Description |
---|
ConcatenateGraphFilter(TokenStream inputTokenStream)
Creates a token stream to convert
input to a token stream
of accepted strings by its token stream graph. |
ConcatenateGraphFilter(TokenStream inputTokenStream,
boolean preserveSep,
boolean preservePositionIncrements,
int maxGraphExpansions)
Creates a token stream to convert
input to a token stream
of accepted strings by its token stream graph. |
Modifier and Type | Method and Description |
---|---|
void |
close()
Releases resources associated with this stream.
|
void |
end()
This method is called by the consumer after the last token has been
consumed, after
TokenStream.incrementToken() returned false
(using the new TokenStream API). |
boolean |
incrementToken()
Consumers (i.e.,
IndexWriter ) use this method to advance the stream to
the next token. |
private static Automaton |
replaceSep(Automaton a,
boolean preserveSep,
int sepLabel) |
void |
reset()
This method is called by a consumer before it begins consumption using
TokenStream.incrementToken() . |
Automaton |
toAutomaton()
Converts the tokenStream to an automaton, treating the transition labels as utf-8.
|
Automaton |
toAutomaton(boolean unicodeAware)
Converts the tokenStream to an automaton.
|
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString
public static final int SEP_LABEL
preserveSep
is true
.public static final int DEFAULT_MAX_GRAPH_EXPANSIONS
public static final boolean DEFAULT_PRESERVE_SEP
public static final boolean DEFAULT_PRESERVE_POSITION_INCREMENTS
private final ConcatenateGraphFilter.BytesRefBuilderTermAttribute bytesAtt
private final PositionIncrementAttribute posIncrAtt
private final OffsetAttribute offsetAtt
private final TokenStream inputTokenStream
private final boolean preserveSep
private final boolean preservePositionIncrements
private final int maxGraphExpansions
private LimitedFiniteStringsIterator finiteStrings
private CharTermAttribute charTermAttribute
private boolean wasReset
private int endOffset
public ConcatenateGraphFilter(TokenStream inputTokenStream)
input
to a token stream
of accepted strings by its token stream graph.
This constructor uses the default settings of the constants in this class.
public ConcatenateGraphFilter(TokenStream inputTokenStream, boolean preserveSep, boolean preservePositionIncrements, int maxGraphExpansions)
input
to a token stream
of accepted strings by its token stream graph.inputTokenStream
- The input/incoming TokenStreampreserveSep
- Whether SEP_LABEL
should separate the input tokens in the concatenated tokenpreservePositionIncrements
- Whether to add an empty token for missing positions.
The effect is a consecutive SEP_LABEL
.
When false, it's as if there were no missing positions
(we pretend the surrounding tokens were adjacent).maxGraphExpansions
- If the tokenStream graph has more than this many possible paths through, then we'll throw
TooComplexToDeterminizeException
to preserve the stability and memory of the
machine.TooComplexToDeterminizeException
- if the tokenStream graph has more than maxGraphExpansions
expansionspublic void reset() throws java.io.IOException
TokenStream
TokenStream.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
throw IllegalStateException
on further usage).
reset
in class TokenStream
java.io.IOException
public boolean incrementToken() throws java.io.IOException
TokenStream
IndexWriter
) use this method to advance the stream to
the next token. Implementing classes must implement this method and update
the appropriate AttributeImpl
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)
and AttributeSource.getAttribute(Class)
,
references to all AttributeImpl
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()
.
incrementToken
in class TokenStream
java.io.IOException
public void end() throws java.io.IOException
TokenStream
TokenStream.incrementToken()
returned false
(using the new TokenStream
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()
.
end
in class TokenStream
java.io.IOException
- If an I/O error occurspublic void close() throws java.io.IOException
TokenStream
If you override this method, always call super.close()
, otherwise
some internal state will not be correctly reset (e.g., Tokenizer
will
throw IllegalStateException
on reuse).
close
in interface java.io.Closeable
close
in interface java.lang.AutoCloseable
close
in class TokenStream
java.io.IOException
public Automaton toAutomaton() throws java.io.IOException
java.io.IOException
public Automaton toAutomaton(boolean unicodeAware) throws java.io.IOException
java.io.IOException