void map ( ByteBuffer buffer ) { if ( ! ( reader instanceof MappedJournalSegmentReader ) ) { JournalReader < E > reader = this . reader ; this . reader = new MappedJournalSegmentReader <> ( buffer , segment , maxEntrySize , index , namespace ) ; this . reader . reset ( reader . getNextIndex ( ) ) ; reader . close ( ) ; } }
Converts the reader to a mapped reader using the given buffer .