||An archive is a concrete collection which is immutable.
||This class provides a basic implementation of the ArchiveMaker
interface, offering only the GAR archives currently in use
(that is ZIP compression, extension .gar)
||A concrete collection typically represents the bottom of a
||A concrete VFile is one which represents an actual file
and is responsible for streaming it from some medium upon
||A dependent collection is a meta collection which stores
dependency information for the layers below it.
||This class represents a .garx descriptor of a remote archive.
||A directory is a file collection created at initialisation
time from a directory on the locally visible filesystem
||A generated collection is one which catches some files deployed
into it, and uses them to generate other files which it passes
||A history collection stores information about which sources have
provided a given vfile in the underlying collection layers, and
provides a means to rollback state after failed installed.
||A layout collection classifies an underlying raw (untyped) collection
according to its file layout.
||A meta collection does not provide any different files than the
layers below it, instead it stores properties of the lower
||A meta vfile encapsulates another vfile, but adds additional information
to it that is only meaningful within its own layer.
||A policy collection is a meta layer that will block file additions
if they conflict with the supplied policy
||A remote archive represents an archive that is not physically
available on the local machine by default.
||A ZIP archive is an archive managing ZIP compressed files.