Re: [Openjnlp-devel] Instant class download :

[Kevin H. <ke...@na...>]

On Monday, December 3, 2001, at 11:40 , David Yen wrote:

> Hi !
>    Is there any way to download class files (maybe not the whole 
> application) by using JNLP programmatically without using web browser?

OpenJNLP is designed to be used as an embedded library as well as a 
standalone application. You could easily write a specialized client that 
would know what app(s) to look for. The OpenJNLP cache is designed 
around a "Reference", which contains details about an application (e.g., 
which jars, description, etc.). You could manually construct your own 
Reference and use that. Or, by taking advantage of the JNLPParser, just 
use a JNLP file and let the JNLPParser create the Reference.

>   Let me draw a scenario here.
>
> A is the control server and download server
> B1, B2, B3 are the clients.
>
> When B1 boot it, it has some configuration file to tell the IP of 
> download server.  A tell B1 to do something and B1 does not have the 
> necessary class, can B1 download class files off the A?

JNLP is jar-based, not class-based. You'd have to package your classes 
into one or more jars. OpenJNLP just added last-modified date 
versioning, so it only downloads each jar only when a new version is 
available. With JNLP out-of-date jars are downloaded, not the entire app.

The next version of OpenJNLP with last-modified versioning is in CVS 
right now and will be issued as a release within a couple of days.