Hi Don,
Don Murray writes:
> >From: Bill Hibbard <hibbard@xxxxxxxxxxxxxxxxx>
> >Organization: SSEC
> >Keywords: 200007121209.e6CC9eT00155
>
> Mike/Bill -
>
> >> Does anyone know if someone is working on providing DODS data
> >> reading capability for VisAD?
> >> http://www.unidata.ucar.edu/packages/dods/index.html
> >
> >We discussed this among the folks at SSEC and Unidata. It
> >is a question of how similar the Java APIs for DODS and netCDF
> >are. I think someone said the C APIs are identical, but that
> >this is not true for their Java APIs. At any rate, the trick
> >would be to exploit the existing netCDF adapter for VisAD to
> >access DODS servers.
> >
> >Perhaps one of the experts from Unidata can comment.
>
> At first glance, one would think they could just use the DODS
> HTTP request using netCDF format and it should seamlessly go into
> VisAD. However, that is not the case because the Java netCDF API
> does not support access to a remote file using the NetcdfFile class
> which is what the VisAD netCDF adapter (Plain) uses.
Another reason this wouldn't work on a DODS URL is because the data
returned is not in netCDF format. (Don: what you and I looked at was
removing the DODS part of the URL and just trying to access a web
accessible netCDF file via HTTP.) For a DODS access in VisAD to work,
there would have to be some DODS client software on the VisAD end.
Either, as I described in my earlier note, a DODS version of the Java
netCDF library or, now that I think of it, the more direct route of
making a VisAD DODS adaptor that calls the DODS Java API.
We've thought more about the first option than the second because:
option one would also be valuable outside the VisAD community; and
with option two, the use of attribute conventions would have to be
added instead of taking advantage of the netCDF conventions already
in the VisAD netCDF adaptor.
Ethan
--
Ethan R. Davis Telephone: (303) 497-8155
Software Engineer Fax: (303) 497-8690
UCAR Unidata Program Center E-mail: edavis@xxxxxxxx
P.O. Box 3000
Boulder, CO 80307-3000 http://www.unidata.ucar.edu/
