Re: running visad program as an applet

• To: bader al-mulla <b_almulla@xxxxxxxxx>
• Subject: Re: running visad program as an applet
• From: Curtis Rueden <curtis@xxxxxxxxxxxxx>
• Date: Tue, 18 Apr 2000 18:58:51 -0500

>can i run a visad program as an applet?
>if yes, how can i run example P3_09 in the visad
>tutorial as an applet?

Bader,

Right now, using VisAD inside an applet is not easy.  There
are a few different ways to approach the problem.

The first is to download the Java Plug-in from Sun's web site
and set it up in your browser, so that you can use Sun's JRE
together with Java3D, all from within an applet.  Then, all
you have to do is write your applet to use a VisAD display,
and it should work great.  However, anyone else that wants to
use your applet will have to install the Java Plug-in as well.
Since I have never tried the Java Plug-in myself, I cannot
offer any more detailed instructions on how to use it.

The second is to write an applet that is a "slave display" to
a VisAD display available on a server.  We have recently added
a class called visad.SocketServer to VisAD, that lets applets
connect and receive display information through a network
socket.  Unfortunately, untrusted applets can only connect to
their codebase machine (the one from which they are being
served), so you'd have to either grant your applet trusted
status, run your SocketServer on the codebase machine, or else
run a proxy server on the codebase machine through which the
SocketServer and applet could communicate indirectly.  We've
written a sample applet that communicates with a SocketServer.
You can find it in visad/examples/VisADApplet.java.

You can create a SocketServer with visad/examples/Test68,
then connect to the server using the VisADApplet program.
However, VisAD browser support is my current project, and
SocketServer is still in development stages.  It is extremely
slow, and does not work correctly on some systems.  Before you
proceed with VisAD-based applets, I recommend you wait until
either VisAD has better browser logic or browsers have better
support for JDK 1.2 and Java3D.

Lastly, the new Netscape beta (Navigator v6.0) supposedly
supports JDK 1.3, although honestly, I haven't gotten Java
working in the new beta at all, much less gotten VisAD working
with it.  If you decide to try it and you have any success,
I'd be interested in hearing how you got it working.

Curtis

• References:
  • running visad program as an applet
    • From: bader al-mulla