NGramTokenFilter

Tokenizes the input into n-grams of the given size(s). As of Lucene 4.4, this token filter:

• handles supplementary characters correctly,
• emits all n-grams for the same token at the same position,
• does not modify offsets,
• sorts n-grams by their offset in the original token first, then increasing length (meaning that "abc" will give "a", "ab", "abc", "b", "bc", "c").

If you were using this [TokenFilter] to perform partial highlighting, this won't work anymore since this filter doesn't update offsets. You should modify your analysis chain to use [NGramTokenizer], and potentially override [NGramTokenizer.isTokenChar] to perform pre-tokenization.