自定義fieldType時，通常還會用到filter。filter必須跟在tokenizer或其它filter之後。如：

<fieldType>
    <analyzer>
        <tokenizer class="solr.StandardTokenizerFactory"/>
        <filter class="solr.LowerCaseFilterFactory" />
    </analyzer>
</fieldType>

Solr 提供了很多的filter，具體如下：

1. ASCII Folding Filter

2. Beider-Morse Filter

3. Classic Filter

4. Common Grams Filter

5. Collation Key Filter

6. Daitch-Mokotoff Soundex Filter

7. Double Metaphone Filter

8. Edge N-Gram Filter

9. English Minimal Stem Filter

10. English Possessive Filter

11. Fingerprint Filter

12. Flatten Graph Filter

13. Hunspell Stem Filter

14. Hyphenated Words Filter

15. ICU Folding Filter

16. ICU Normalizer 2 Filter

17. ICU Transform Filter

18. Keep Word Filter

19. KStem Filter

20. Length Filter

21. Limit Token Count Filter

22. Limit Token Offset Filter

23. Limit Token Position Filter

24. Lower Case Filter

25. Managed Stop Filter

26. Managed Synonym Filter

27. N-Gram Filter

28. Numeric Payload Token Filter

29. Pattern Replace Filter

30. Phonetic Filter

31. Porter Stem Filter

32. Remove Duplicated Token Filter

33. Reversed Wildcard Filter

34. Shingle Filter

35. Snowball Porter Stemmer Filter

36. Standard Filter

37. Stop Filter

38. Suggest Stop Filter

39. Synonym Filter

40. Synonym Graph Filter

41. Token Offset Payload Filter

42. Trim Filter

43. Type As Payload Filter

44. Type Token Filter

45. Word Delimiter Filter

46. Word Delimiter Graph Filter

Solr 6.7學習筆記（02）-- 配置文件 managed-schema (schema.xml) - filter（5）