Class SnowballFilter

  • All Implemented Interfaces:
    java.io.Closeable, java.lang.AutoCloseable

    public final class SnowballFilter
    extends TokenFilter
    A filter that stems words using a Snowball-generated stemmer. Available stemmers are listed in org.tartarus.snowball.ext.

    NOTE: SnowballFilter expects lowercased text.

    Note: This filter is aware of the KeywordAttribute. To prevent certain terms from being passed to the stemmer KeywordAttribute.isKeyword() should be set to true in a previous TokenStream. Note: For including the original term as well as the stemmed version, see KeywordRepeatFilterFactory

    • Constructor Detail

      • SnowballFilter

        public SnowballFilter​(TokenStream input,
                              org.tartarus.snowball.SnowballProgram stemmer)
      • SnowballFilter

        public SnowballFilter​(TokenStream in,
                              java.lang.String name)
        Construct the named stemming filter. Available stemmers are listed in org.tartarus.snowball.ext. The name of a stemmer is the part of the class name before "Stemmer", e.g., the stemmer in EnglishStemmer is named "English".
        Parameters:
        in - the input tokens to stem
        name - the name of a stemmer
    • Method Detail

      • incrementToken

        public final boolean incrementToken()
                                     throws java.io.IOException
        Returns the next input Token, after being stemmed
        Specified by:
        incrementToken in class TokenStream
        Returns:
        false for end of stream; true otherwise
        Throws:
        java.io.IOException