org.apache.lucene.analysis.miscellaneous
Class SingleTokenTokenStream

java.lang.Object
  extended by org.apache.lucene.analysis.TokenStream
      extended by org.apache.lucene.analysis.miscellaneous.SingleTokenTokenStream

public class SingleTokenTokenStream
extends TokenStream

A token stream containing a single token.


Constructor Summary
SingleTokenTokenStream(Token token)
           
 
Method Summary
 Token getToken()
           
 Token next(Token reusableToken)
          Returns the next token in the stream, or null at EOS.
 void reset()
          Resets this stream to the beginning.
 void setToken(Token token)
           
 
Methods inherited from class org.apache.lucene.analysis.TokenStream
close, next
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SingleTokenTokenStream

public SingleTokenTokenStream(Token token)
Method Detail

next

public Token next(Token reusableToken)
           throws IOException
Description copied from class: TokenStream
Returns the next token in the stream, or null at EOS. When possible, the input Token should be used as the returned Token (this gives fastest tokenization performance), but this is not required and a new Token may be returned. Callers may re-use a single Token instance for successive calls to this method.

This implicitly defines a "contract" between consumers (callers of this method) and producers (implementations of this method that are the source for tokens):

Also, the producer must make no assumptions about a Token after it has been returned: the caller may arbitrarily change it. If the producer needs to hold onto the token for subsequent calls, it must clone() it before storing it. Note that a TokenFilter is considered a consumer.

Overrides:
next in class TokenStream
Parameters:
reusableToken - a Token that may or may not be used to return; this parameter should never be null (the callee is not required to check for null before using it, but it is a good idea to assert that it is not null.)
Returns:
next token in the stream or null if end-of-stream was hit
Throws:
IOException

reset

public void reset()
           throws IOException
Description copied from class: TokenStream
Resets this stream to the beginning. This is an optional operation, so subclasses may or may not implement this method. Reset() is not needed for the standard indexing process. However, if the Tokens of a TokenStream are intended to be consumed more than once, it is necessary to implement reset(). Note that if your TokenStream caches tokens and feeds them back again after a reset, it is imperative that you clone the tokens when you store them away (on the first pass) as well as when you return them (on future passes after reset()).

Overrides:
reset in class TokenStream
Throws:
IOException

getToken

public Token getToken()

setToken

public void setToken(Token token)


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