Class PatternTokenizerFactory

Factory for PatternTokenizer. This tokenizer uses regex pattern matching to construct distinct tokens for the input stream. It takes two arguments: "pattern" and "group".

• "pattern" is the regular expression.
• "group" says which group to extract into tokens.

group=-1 (the default) is equivalent to "split". In this case, the tokens will be equivalent to the output from (without empty tokens): System.Text.RegularExpressions.Regex.Replace(System.String,System.String)

Using group >= 0 selects the matching group as the token. For example, if you have:

    pattern = \'([^\']+)\'
    group = 0
    input = aaa 'bbb' 'ccc'

the output will be two tokens: 'bbb' and 'ccc' (including the ' marks). With the same input but using group=1, the output would be: bbb and ccc (no ' marks)

NOTE: This Tokenizer does not output tokens that are of zero length.

<fieldType name="text_ptn" class="solr.TextField" positionIncrementGap="100">
  <analyzer>
    <tokenizer class="solr.PatternTokenizerFactory" pattern="\'([^\']+)\'" group="1"/>
  </analyzer>
</fieldType>

@since solr1.2