public final class SynonymGraphFilter extends TokenFilter
SynonymMapto an incoming
TokenStream, producing a fully correct graph output. This is a replacement for
SynonymFilter, which produces incorrect graphs for multi-token synonyms.
However, if you use this during indexing, you must follow it with
FlattenGraphFilter to squash tokens on top of one another
SynonymFilter, because the indexer can't directly
consume a graph. To get fully correct positional queries when your
synonym replacements are multiple tokens, you should instead apply
synonyms using this
TokenFilter at query time and translate
the resulting graph to a
TermAutomatonQuery e.g. using
NOTE: this cannot consume an incoming graph; results will be undefined.
|Modifier and Type||Field and Description|
|Constructor and Description|
|Modifier and Type||Method and Description|
This method is called by a consumer before it begins consumption using
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString
public boolean incrementToken() throws IOException
IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate
AttributeImpls 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
references to all
AttributeImpls 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
public void reset() throws IOException
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.
The default implementation chains the call to the input TokenStream, so
be sure to call
super.reset() when overriding this method.