Apache Lucene 6.2.1 发布了，修复了上个版本的3个bug
LUCENE-7417: The standard Highlighter could throw an IllegalArgumentException when trying to highlight a query containing a degenerate case of a MultiPhraseQuery with one term.
LUCENE-7440: Document id skipping (PostingsEnum.advance) could throw an ArrayIndexOutOfBoundsException exception on large index segments (>1.8B docs) with large skips.
LUCENE-7318: Fix backwards compatibility issues around StandardAnalyzer and its components, introduced with Lucene 6.2.0. The moved classes were restored in their original packages: LowercaseFilter and StopFilter, as well as several utility classes.