public final class TeeSinkTokenFilter extends TokenFilter
TeeSinkTokenFilter source1 = new TeeSinkTokenFilter(new WhitespaceTokenizer(reader1)); TeeSinkTokenFilter.SinkTokenStream sink1 = source1.newSinkTokenStream(); TeeSinkTokenFilter.SinkTokenStream sink2 = source1.newSinkTokenStream(); TeeSinkTokenFilter source2 = new TeeSinkTokenFilter(new WhitespaceTokenizer(reader2)); source2.addSinkTokenStream(sink1); source2.addSinkTokenStream(sink2); TokenStream final1 = new LowerCaseFilter(source1); TokenStream final2 = source2; TokenStream final3 = new EntityDetect(sink1); TokenStream final4 = new URLDetect(sink2); d.add(new Field("f1", final1)); d.add(new Field("f2", final2)); d.add(new Field("f3", final3)); d.add(new Field("f4", final4));In this example,
sink1
and sink2
will both get tokens from both
reader1
and reader2
after whitespace tokenizer
and now we can further wrap any of these in extra analysis, and more "sources" can be inserted if desired.
It is important, that tees are consumed before sinks (in the above example, the field names must be
less the sink's field names). If you are not sure, which stream is consumed first, you can simply
add another sink and then pass all tokens to the sinks at once using consumeAllTokens()
.
This TokenFilter is exhausted after this. In the above example, change
the example above to:
... TokenStream final1 = new LowerCaseFilter(source1.newSinkTokenStream()); TokenStream final2 = source2.newSinkTokenStream(); sink1.consumeAllTokens(); sink2.consumeAllTokens(); ...In this case, the fields can be added in any order, because the sources are not used anymore and all sinks are ready.
Note, the EntityDetect and URLDetect TokenStreams are for the example and do not currently exist in Lucene.
Modifier and Type | Class and Description |
---|---|
static class |
TeeSinkTokenFilter.SinkFilter
A filter that decides which
AttributeSource states to store in the sink. |
static class |
TeeSinkTokenFilter.SinkTokenStream
TokenStream output from a tee with optional filtering.
|
AttributeSource.AttributeFactory, AttributeSource.State
input
Constructor and Description |
---|
TeeSinkTokenFilter(TokenStream input)
Instantiates a new TeeSinkTokenFilter.
|
Modifier and Type | Method and Description |
---|---|
void |
addSinkTokenStream(TeeSinkTokenFilter.SinkTokenStream sink)
Adds a
TeeSinkTokenFilter.SinkTokenStream created by another TeeSinkTokenFilter
to this one. |
void |
consumeAllTokens()
TeeSinkTokenFilter passes all tokens to the added sinks
when itself is consumed. |
void |
end()
Performs end-of-stream operations, if any, and calls then
end() on the
input TokenStream. |
boolean |
incrementToken()
Consumers (i.e.,
IndexWriter ) use this method to advance the stream to
the next token. |
TeeSinkTokenFilter.SinkTokenStream |
newSinkTokenStream()
Returns a new
TeeSinkTokenFilter.SinkTokenStream that receives all tokens consumed by this stream. |
TeeSinkTokenFilter.SinkTokenStream |
newSinkTokenStream(TeeSinkTokenFilter.SinkFilter filter)
Returns a new
TeeSinkTokenFilter.SinkTokenStream that receives all tokens consumed by this stream
that pass the supplied filter. |
close, reset
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, restoreState, toString
public TeeSinkTokenFilter(TokenStream input)
public TeeSinkTokenFilter.SinkTokenStream newSinkTokenStream()
TeeSinkTokenFilter.SinkTokenStream
that receives all tokens consumed by this stream.public TeeSinkTokenFilter.SinkTokenStream newSinkTokenStream(TeeSinkTokenFilter.SinkFilter filter)
TeeSinkTokenFilter.SinkTokenStream
that receives all tokens consumed by this stream
that pass the supplied filter.TeeSinkTokenFilter.SinkFilter
public void addSinkTokenStream(TeeSinkTokenFilter.SinkTokenStream sink)
TeeSinkTokenFilter.SinkTokenStream
created by another TeeSinkTokenFilter
to this one. The supplied stream will also receive all consumed tokens.
This method can be used to pass tokens from two different tees to one sink.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, but all sinks are instant available.IOException
public boolean incrementToken() throws 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
IOException
public final void end() throws IOException
TokenFilter
end()
on the
input TokenStream.
NOTE: Be sure to call super.end()
first when overriding this method.end
in class TokenFilter
IOException