|
ACDK implementation of acdk::io::File is a fassade to a virtual file system.
ACDK File related classes Java java.io.File In Java the file java.io.File
provides access to a File, whereas the file located on the normal operations system file system.
ACDK acdk::io::File In ACDK files addressed with acdk::io::File can also be
located in the local ressources of the executable, a file in an archive,
like TAR or ZIP files, or can be located on a remote machine accessible via
FTP or HTTP.
The framework classes Behind of the fassade of the class File following
interfaces build the functionality of files:
- interface
 acdk::io::FileSystem.
The FileSystem holds the files and implements the basic file functionalities.
- interface acdk::io::FileImpl.
With this interface the functionality of acdk::io::File will be implemented.
- interface acdk::io::FileSystemFactory.
The FileSystemFactory returns the FileSystem, which handles a given file by name.
Virtual file system naming follows two conventions:
- URLs identify root file systems (like
http:// or ftp://)
- container identifies files, which contains own internal file system
like zip or tar archives. Container file systems are identified by a
path/file.fileextension@ wheras the significant part is .fileextension@.
File names are addresses The internet introduces the concept of URL's - unified ressource locator.
The URL concept describes method of access (ftp, http, email, etc.) and the location.
- /home/roger/tmp/file.txt is a normal local file
- /home/roger/tmp/archive.zip is a normal local file too
- /home/roger/tmp/archive.zip@ is the root directory of the
internal file system contained in the archive.zip.
- .ressource@/com/artefaktur/test/file.dat is a file in the internal ressource file system
- ftp://ftp.artefaktur.ch/acdk is a directory on the ftp file system located at ftp.artefaktur.ch.
- .ressouce@/com/artefaktur/archive.zip@dir/file.txt is file in an archive file system, which itself resides in the internal ressource file system.
".ressource@com/artefaktur/my/file"
- ".ressource@" is the file system prefix.
- "com/artefaktur/my" is the directory
- "file" is the file name.
/home/roger/myarchive.zip@mydir/sub/myfile.dat
where
- /home/roger/myarchive.zip is an existent file
- mydir/sub the directory in the archive
- the file in the archive. myfile.dat
Please refer to
TAR files are addressed following way:
/home/roger/myarchive.tar@mydir/sub/myfile.dat
where
- /home/roger/myarchive.tar is an existent file
- mydir/sub the directory in the archive
- the file in the archive. myfile.dat
HTTP files are identified by a url http://domain.net/path/file.
This file system only supports reading a file. Directory or modification
operations are not supported.
The FTP file system is identified by a url ftp://domain.net/path/file_or_dir
Not all operations on FTP files are supported.
 The Simple Remote Filesystem is a traditional
TCP/IP based remote file system used inhouse to synchronize complete directories.
The implementation of the different file systems are located in dll/shared libraries.
In the configuration (%ACDKHOME/cfg/acdk.cfg by default) these file systems are
registered:
Sample:
acdk.io.filesystem.protocol.container.0=.zip@=acdk/vfile/zip/ZipFileSystemFactory
acdk.io.filesystem.protocol.container.1=.ZIP@=acdk/vfile/zip/ZipFileSystemFactory
acdk.io.filesystem.protocol.container.2=.tar@=acdk/vfile/tar/TarFileSystemFactory
acdk.io.filesystem.protocol.container.3=.TAR@=acdk/vfile/zip/TarFileSystemFactory
# filename has to start with the url
acdk.io.filesystem.protocol.url.0=ftp://=acdk/net/ftp/FTPFileSystemFactory
acdk.io.filesystem.protocol.url.1=http://=acdk/net/UrlFileSystemFactory
If a acdk::io::File instance will be created with a matching naming pattern (url or container)
the acdk class loader will load the corresponding factory classes.
|
2005/5/10
acdk::io::FileSystem
Overview