Package org.apache.lucene.analysis.position

Class PositionFilter

  • All Implemented Interfaces:
    java.io.Closeable, java.lang.AutoCloseable
    @Deprecated
public final class PositionFilter
extends TokenFilter
    Deprecated.
    (4.4) PositionFilter makes TokenStream graphs inconsistent which can cause highlighting bugs. Its main use-case being to make QueryParser generate boolean queries instead of phrase queries, it is now advised to use QueryParser.setAutoGeneratePhraseQueries(boolean) (for simple cases) or to override QueryParser.newFieldQuery.
    Set the positionIncrement of all tokens to the "positionIncrement", except the first return token which retains its original positionIncrement value. The default positionIncrement value is zero.

    • Constructor Detail

      • PositionFilter

        public PositionFilter​(TokenStream input)
        Deprecated.
        Constructs a PositionFilter that assigns a position increment of zero to all but the first token from the given input stream.
        Parameters:
        input - the input stream

      • PositionFilter

        public PositionFilter​(TokenStream input,
                      int positionIncrement)
        Deprecated.
        Constructs a PositionFilter that assigns the given position increment to all but the first token from the given input stream.
        Parameters:
        input - the input stream
        positionIncrement - position increment to assign to all but the first token from the input stream

    • Method Detail

      • incrementToken

        public final boolean incrementToken()
                             throws java.io.IOException
        Deprecated.
        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:
        java.io.IOException

      • reset

        public void reset()
           throws java.io.IOException
        Deprecated.
        Description copied from class: TokenFilter
        This method is called by a consumer before it begins consumption using 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).

        NOTE: The default implementation chains the call to the input TokenStream, so be sure to call super.reset() when overriding this method.

        Overrides:
        reset in class TokenFilter
        Throws:
        java.io.IOException