Recordcache provides abstractions around building and reading lsmtrees.
RecordLogAppender is used to write record logs.
RecordLogDirectoryPoller provides an iterator over record logs built by RecordLogAppender. It is typically used in conjunction with RecordCache to build lsmtrees. It persists the last position it processes so it can begin where it left off from previous runs.
RecordCache is an interface for performing lookups. There are two implementations.
PersistentRecordCache builds an lsmtree of key -> record log position. When performing lookups it uses the lsmtree as indirection into record logs to get the values.
MemcachedMappingRecordCache is a wrapper around PersistentRecordCache that uses memcached to eagerly cache new record log entries and any missed lookups.
RecordLogStore is a simple wrapper around a Store, RecordLogDirectory, and RecordLogDirectoryPoller.
ReplicatingStoreBuilder is a builder that creates a RecordLogStore. The store builds an lsmtree of key -> value and avoids the indirection of PersistentRecordCache. It deletes the underlying record logs after their contents have been written into the lsmtree.