org.apache.spark.sql.execution.streaming
A custom hash map used to track the list of files seen.
A custom hash map used to track the list of files seen. This map is not thread-safe.
To prevent the hash map from growing indefinitely, a purge function is available to remove files "maxAgeMs" older than the latest file.
Timestamp for file modification time, in ms since January 1, 1970 UTC.