Class GreekLowerCaseFilter

  • All Implemented Interfaces:, java.lang.AutoCloseable

    public final class GreekLowerCaseFilter
    extends TokenFilter
    Normalizes token text to lower case, removes some Greek diacritics, and standardizes final sigma to sigma.

    You must specify the required Version compatibility when creating GreekLowerCaseFilter:

    • As of 3.1, supplementary characters are properly lowercased.
    • Constructor Detail

      • GreekLowerCaseFilter

        public GreekLowerCaseFilter​(Version matchVersion,
                                    TokenStream in)
        Create a GreekLowerCaseFilter that normalizes Greek token text.
        matchVersion - Lucene compatibility version, See above
        in - TokenStream to filter
    • Method Detail

      • incrementToken

        public boolean incrementToken()
        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
        false for end of stream; true otherwise