question: protected RrdNioBackend ( String path , boolean readOnly , int syncPeriod ) throws IOException { super ( path , readOnly ) ; try { mapFile ( ) ; if ( ! readOnly ) { fileSyncTimer . schedule ( syncTask , syncPeriod * 1000L , syncPeriod * 1000L ) ; } } catch ( final IOException ioe ) { super . close ( ) ; throw ioe ; } }
target:  Creates RrdFileBackend object for the given file path, backed by java.nio.* classes.