[jcifs] smb protocol handler

[Michael B. Allen]

Very interesting. Where are the attached files?


On Tue, 24 Dec 2002 13:35:08 +0100
"Marc Hoffmann" <marc.hoffmann at mountainminds.com> wrote:

> 
> Hi Mike,
> 
> my name is Marc Hoffmann, working with Fujitsu EST GmbH, located in Munich.
> The company uses JCIFS for a while internally in one of their Java APIs (see
> conversation with Uwe Specht regarding closed pipes).
> 
> 
> PROBLEM
> 
> The new URL design of version 0.7 introduces Java's powerful extension
> mechanism for new protocol types, but has also a serious impact on system
> properties and class loading (see e.g. "MalformedURLException" threads).
> Especially in the context of application servers this adds deployment
> hassles. Moreover, if necessary modifications of the security settings or
> system libraries are not possible this could become a "show stopper".
> 
> 
> SUGGESTION
> 
> Therefore I would like to suggest making the registration of the URL handler
> optional. It could explicitly triggered by an application by invoking a
> static method like "Config.registerSmbURLHandler()".
> 
> To grant backward capability (concerning deployment) and allow standard
> deployment of e.g. web applications the internal JCIFS implementation should
> not rely on the registration of an URLStreamHandler.
> 
> 
> IMPLEMENTATION
> 
> The 0.7.0b10 implementation could easily be changed to work without the need
> of the registered smb protocol. The basic idea is to explicitly pass the
> proper URLStreamHandler directly to the internally used java.net.URL
> constructors. Some testing proofed that the MalformedURLException does not
> happen, even if no system property is set and the jcifs.jar is located in
> the WEB-INF/lib of a web application only.
> 
> I made the following modifications (source files attached):
> 
> 1. Provide an internally used singleton instance of jcifs.smb.Handler:
> 
>   static final URLStreamHandler SMB_HANDLER = new Handler();
> 
> 2. Replace all URL constructors in SmbFile with the URL(URL context, String
> spec, URLStreamHandler handler) version, e.g.
> 
>     public SmbFile( SmbFile context, String name ) throws
> MalformedURLException, UnknownHostException {
>         this( context.isWorkgroup0() ?
>             new URL(null, "smb://" + name, Handler.SMB_HANDLER) :
>             new URL( context.url, name, Handler.SMB_HANDLER),
> context.auth );
>     }
> 
> 3. In the files SmbFileInputStream, SmbFileOutputStream, SmbNamedPipe
> replace "new SmbFile(new URL(urlstring))" by "new SmbFile(urlstring)".
> 
> This modification would certainly avoid many error situations, especially
> for users who upgrade from older jcifs versions and do not use java.net.URL
> to identify resources at all.
> 
> Best Regards,
> marc
> 


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