public override TokenStream TokenStream(string fieldName, TextReader reader)
{
var attributeSource = new AttributeSource();
attributeSource.AddAttributeImpl(new SpellAttribute());
attributeSource.AddAttributeImpl(new StemAttribute());
var tokenizer = new RussianLetterTokenizer(attributeSource, reader);
var lowercaseFilter = new LowerCaseFilter(tokenizer);
var badWordsFilter = new BadWordsFilter(lowercaseFilter);
var stopWordFilter = new StopFilter(false, badWordsFilter, StopWords);
var preFilter = new StemFilter(stopWordFilter, SpellChecker, NumberOfSuggestions);
var similarFilter = new SimilarFilter(preFilter);
return(similarFilter);
}