Class JapaneseKatakanaStemFilter

  • All Implemented Interfaces:
    Closeable, AutoCloseable

    public final class JapaneseKatakanaStemFilter
    extends org.apache.lucene.analysis.TokenFilter
    A TokenFilter that normalizes common katakana spelling variations ending in a long sound character by removing this character (U+30FC). Only katakana words longer than a minimum length are stemmed (default is four).

    Note that only full-width katakana characters are supported. Please use a CJKWidthFilter to convert half-width katakana to full-width before using this filter.

    In order to prevent terms from being stemmed, use an instance of KeywordMarkerFilter or a custom TokenFilter that sets the KeywordAttribute before this TokenStream.

    • Nested Class Summary

      • Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource

        org.apache.lucene.util.AttributeSource.AttributeFactory, org.apache.lucene.util.AttributeSource.State
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int DEFAULT_MINIMUM_LENGTH  
      • Fields inherited from class org.apache.lucene.analysis.TokenFilter

        input
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean incrementToken()  
      • Methods inherited from class org.apache.lucene.analysis.TokenFilter

        close, end, reset
      • Methods inherited from class org.apache.lucene.util.AttributeSource

        addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, restoreState, toString
    • Field Detail

    • Constructor Detail

      • JapaneseKatakanaStemFilter

        public JapaneseKatakanaStemFilter​(org.apache.lucene.analysis.TokenStream input,
                                          int minimumLength)
      • JapaneseKatakanaStemFilter

        public JapaneseKatakanaStemFilter​(org.apache.lucene.analysis.TokenStream input)
    • Method Detail

      • incrementToken

        public boolean incrementToken()
                               throws IOException
        Specified by:
        incrementToken in class org.apache.lucene.analysis.TokenStream
        Throws:
        IOException