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From Andy Thomson <a10008...@gmail.com>
Subject Re: [jira] Created: (FTPSERVER-189) After the renaming FileObject->FtpFile the method FileSystemView#getFileObject should renamed
Date Mon, 06 Oct 2008 02:06:59 GMT
Andrea,

This makes sense if the base file systems is/are a real file system. The 
Native File System being such a case.

However it does not make sense if using a JDBC, Persistence, Virtual 
File System, or even an FTP Proxy.  In these cases, the files are really 
Objects, not "tangible" files located on a disk drive.  It's really more 
than just a name change or semantic, it's the intent, what it 
[FileObject], really represents.

I suspect there are two issues here that are confusing?

  1) File Metadata
  2) File Content

These are not always in the same location, more often than not, they are 
not together in a virtual or distributed system.  In these, the metadata 
is typically in a database, and the content is on some remote storage 
system, NetApps Filer, EMC Centera, Sun Thumper, SAN, Windows Server, or 
even another FTP Server [local disks].

The FileObject accurately represents what the FTP server is actually 
handling, file metadata and file content, where the two may not be 
physically located together. In other words, the FileObject is purposely 
abstract about each, providing flexibility to handle different approaches.

When I first started working with the code, I too thought the same thing 
when I first saw this. Huh?, FileObject? Hey, I'll make it a File not 
FileObject, then I realized what was going on, and said to myself, hey 
whoever did this was thinking ahead.

This is a little off topic, but it is related. Think about it this way, 
a FileObject typically has only one copy of metadata, but it can have 
many copies of the file content located on different storage devices. 
Simply changing the stream from a local disk to a url-stream allows 
access to those copies.  Why is this important? For some it's about 
having multiple back-up copies in the case if a disaster, for others it 
might be near and distant data center and costs access to them.

See the intent behind the FileObject? It's flexible, not only in code, 
but also in thought.

In my opinion, I would leave the FileObject as-is, if it's really 
causing issues, make changes in a local copy.  I suspect though, that as 
the world moves to more object-based storage, the local changes will be 
a major problem.  It's not just a simple name change, it's what it 
represents :-).

... my two-cents worth

Andy Thomson























Andrea Francia (JIRA) wrote:
> After the renaming FileObject->FtpFile the method FileSystemView#getFileObject should
renamed
> ---------------------------------------------------------------------------------------------
> 
>                  Key: FTPSERVER-189
>                  URL: https://issues.apache.org/jira/browse/FTPSERVER-189
>              Project: FtpServer
>           Issue Type: Bug
>             Reporter: Andrea Francia
> 
> 
> I propose to rename from:
>     FtpFile getFileObject(String file) throws FtpException;
> to:
>     FtpFile getFile(String path) throws FtpException;
> 
> There is a patch for this.
> 

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