public FileArchiverNotifier get(Connection conn, Configuration conf, FileSystem fs,
    TableName tn) {
    // Ensure that only one instance is exposed to callers
    return CACHE.computeIfAbsent(tn, key -> new FileArchiverNotifierImpl(conn, conf, fs, key));
  }
Returns the {@link FileArchiverNotifier} instance for the given {@link TableName}.
@param tn The table to obtain a notifier for
@return The notifier for the given {@code tablename}.
hbase-server/src/main/java/org/apache/hadoop/hbase/quotas/FileArchiverNotifierFactoryImpl.java