开始

方法二

DirectoryReader.openIfChanged(DirectoryReader oldReader, IndexCommit commit)

IndexWriter

是否为空?

u245_seg0 u245_seg1 u245_seg2 u245_seg3

indexCommit

是否为空?

u247_seg0 u247_seg1 u247_seg2

获得所有段的信息集合

SegmentInfos

u250_seg0 u250_seg1 u250_seg2

结束

返回新的

StandardDirectoryReader

u254_seg0 u254_seg1

找出变更的LeafReader

u256_seg0 u256_seg1
u257_seg0 u257_seg1