This interface is used to query a tree of file stores.
A file tree accurately represents the state of a portion of a file system
at the time it is created, but it is never updated. Clients using a file
tree must tolerate the fact that the actual file system contents may have
changed since the tree was generated.
This interface is not intended to be implemented by clients. File tree
implementations should use the concrete class FileTree
This interface is not intended to be implemented by clients. File tree implementations should use the concrete class FileTree