Constructor Detail

• FilteringTokenFilter

  public FilteringTokenFilter​(boolean enablePositionIncrements,
                              TokenStream input)

Method Detail

• accept

  protected abstract boolean accept()
                             throws IOException

  Override this method and return if the current input token should be returned by incrementToken().

  Throws:

  IOException

• incrementToken

  public final boolean incrementToken()
                               throws 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 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 AttributeSource.addAttribute(Class) and AttributeSource.getAttribute(Class), 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 TokenStream.incrementToken().

  Specified by:

  incrementToken in class TokenStream

  Returns:

  false for end of stream; true otherwise

  Throws:

  IOException

• reset

  public void reset()
             throws IOException

  Description copied from class: TokenFilter
  Reset the filter as well as the input TokenStream.

  Overrides:

  reset in class TokenFilter

  Throws:

  IOException

• getEnablePositionIncrements

  public boolean getEnablePositionIncrements()

  See Also:

  setEnablePositionIncrements(boolean)

• setEnablePositionIncrements

  public void setEnablePositionIncrements​(boolean enable)

  If true, this TokenFilter will preserve positions of the incoming tokens (ie, accumulate and set position increments of the removed tokens). Generally, true is best as it does not lose information (positions of the original tokens) during indexing.

  When set, when a token is stopped (omitted), the position increment of the following token is incremented.

  NOTE: be sure to also set QueryParser.setEnablePositionIncrements(boolean) if you use QueryParser to create queries.