Add files from a directory. This operation is destructive: the cache implementation is allowed to modify the source directory.
Utility function (copy file or directory)
Extract a cache entry to a target directory, with a filter for root files/directories.
Close the cache. Called after all operations are completed and the cache is no longer immediately needed.
Get a list of keys for all cached entries.
Check if an entry with the given key exists.
Get the full file listing for the given cache entry. Forward slashes only.
Optimize the cache (minimize disk space). This operation can be very slow (and should display progress).
Delete a cache entry.
Verify cache integrity.
Get name of this cache engine.
Abstract base class.