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[netCDFJava #VKX-907984]: Need help

Greetings Sailesh,

Apologies for the delay in reply. I've uploaded a java class that reads
the datasets from the xml catalog and prints out the dates from the first
dataset, just as an example:

https://gist.github.com/lesserwhirls/df3d4d4cd51ae0f6a208

Hopefully this will give you a good idea of where to go.

Let me know if you need any help with the example.

Cheers!

Sean

> ?Hello,
> 
> Thanks for the quick reply. I understand that a file cannot be
> completely downloaded using current access methods. But my question is, if
> I provide the same url ?
> http://sflthredds.er.usgs.gov/thredds/catalog/TSdata/surfaces/catalog.
> <http://sflthredds.er.usgs.gov/thredds/catalog/TSdata/surfaces/catalog.html>
> xml
> to EVERVIEW application, I am able to see all the list of .nc files that
> are inside. Also I can look at a particular type of information as you
> mentioned. My requirement here is,
> Suppose I have run my code today,
> 2015_q1.nc would contain the surface water depth data till 02/02/2015, it
> gets downloaded(just suppose). In my next run say on 02/15/2015, The data
> required would be still in 2015_q1.nc, but before downloading the file, I
> need to make sure that the 2015_q1.nc file is updated with the information
> after 02/02/2015(I don't want to use the last modified field though), I
> mean the time axis values of the NETcdf file should contain dates after
> 02/02/2015. For that I really don't have to download the file, only if the
> check passed saying that the file has been updated with more dates, the it
> must be downloaded. So I need a way to look whats inside the catalog and
> the dates inside the .nc file without downloading. Only then I have to
> download the file with the updated data than my previous run. For
> downloading the file, I have to request them to enable HTTP access to
> download the file.
> 
> Could you please let me know if I have stated my problem clearly or you
> need some information.
> 
> Also,
> I see the exception *"java.io.IOException: Server does not support byte
> Ranges" *while trying to open the dataset of that url through a java api is
> because it is not accessible for download through http .
> 
> 
> Thanks,
> Sailesh.
> 
> address@hidden> wrote:
> 
> > Greetings Sailesh,
> >
> > What you wish to do isn't necessarily a trivial task, but it could be done.
> > However, what would be even better is if the owner of the TDS you
> > reference would open up the data files to be served over HTTP, which
> > would allow you to download the entire datafile. The current access
> > methods that are available (OPeNDAP, WCS, WMS, NetcdfSubset
> > service, etc.) are not intended to provide users with a way to download
> > entire files, but rather only specific subsets.
> >
> > The contact info for that server can be found here:
> >
> > http://sflthredds.er.usgs.gov/thredds/serverInfo.html
> >
> > If they will enable HTTP access to download the file, which
> > is a relatively simple change in a configuration file for the TDS,
> > then you could download the files directly. Given the naming
> > convention of the files, it should be easy to figure out which
> > file contains the data you wish to use.
> >
> > Cheers,
> >
> > Sean
> >
> > > Hello,
> > >
> > > I am a graduate student working as a research assistant from university
> > > of louisiana, lafayette. I am trying to write a java program that
> > > downloads netcdf files from thredd server. For instance :
> > >
> > >
> > http://sflthredds.er.usgs.gov/thredds/catalog/TSdata/surfaces/catalog.html
> > >
> > > There are a lot of .nc files starting from 1991_q1.nc to 2015_q1.nc, I
> > am
> > > trying to write a program which takes the above url as input, gets the
> > list
> > > of files present in the catalog, also based on the values of time axis
> > > inside the netcdf file, I need to download all the .nc files for suppose
> > > that have date values after 01/01/2015. Could you please help me writing
> > > that.
> > >
> > > Thanks.
> > > Sailesh.
> > >
> > >
> >
> > Ticket Details
> > ===================
> > Ticket ID: VKX-907984
> > Department: Support netCDF Java
> > Priority: Normal
> > Status: Open
> >
> >
> 
> > ?Hello,
> 
> Thanks for the quick reply. I understand that a file cannot be
> completely downloaded using current access methods. But my question is, if
> I provide the same url ?
> http://sflthredds.er.usgs.gov/thredds/catalog/TSdata/surfaces/catalog.
> <http://sflthredds.er.usgs.gov/thredds/catalog/TSdata/surfaces/catalog.html>
> xml
> to EVERVIEW application, I am able to see all the list of .nc files that
> are inside. Also I can look at a particular type of information as you
> mentioned. My requirement here is,
> Suppose I have run my code today,
> 2015_q1.nc would contain the surface water depth data till 02/02/2015, it
> gets downloaded(just suppose). In my next run say on 02/15/2015, The data
> required would be still in 2015_q1.nc, but before downloading the file, I
> need to make sure that the 2015_q1.nc file is updated with the information
> after 02/02/2015(I don't want to use the last modified field though), I
> mean the time axis values of the NETcdf file should contain dates after
> 02/02/2015. For that I really don't have to download the file, only if the
> check passed saying that the file has been updated with more dates, the it
> must be downloaded. So I need a way to look whats inside the catalog and
> the dates inside the .nc file without downloading. Only then I have to
> download the file with the updated data than my previous run. For
> downloading the file, I have to request them to enable HTTP access to
> download the file.
> 
> Could you please let me know if I have stated my problem clearly or you
> need some information.
> 
> Also,
> I see the exception *"java.io.IOException: Server does not support byte
> Ranges" *while trying to open the dataset of that url through a java api is
> because it is not accessible for download through http .
> 
> 
> Thanks,
> Sailesh.
> 
> address@hidden> wrote:
> 
> > Greetings Sailesh,
> >
> > What you wish to do isn't necessarily a trivial task, but it could be done.
> > However, what would be even better is if the owner of the TDS you
> > reference would open up the data files to be served over HTTP, which
> > would allow you to download the entire datafile. The current access
> > methods that are available (OPeNDAP, WCS, WMS, NetcdfSubset
> > service, etc.) are not intended to provide users with a way to download
> > entire files, but rather only specific subsets.
> >
> > The contact info for that server can be found here:
> >
> > http://sflthredds.er.usgs.gov/thredds/serverInfo.html
> >
> > If they will enable HTTP access to download the file, which
> > is a relatively simple change in a configuration file for the TDS,
> > then you could download the files directly. Given the naming
> > convention of the files, it should be easy to figure out which
> > file contains the data you wish to use.
> >
> > Cheers,
> >
> > Sean
> >
> > > Hello,
> > >
> > > I am a graduate student working as a research assistant from university
> > > of louisiana, lafayette. I am trying to write a java program that
> > > downloads netcdf files from thredd server. For instance :
> > >
> > >
> > http://sflthredds.er.usgs.gov/thredds/catalog/TSdata/surfaces/catalog.html
> > >
> > > There are a lot of .nc files starting from 1991_q1.nc to 2015_q1.nc, I
> > am
> > > trying to write a program which takes the above url as input, gets the
> > list
> > > of files present in the catalog, also based on the values of time axis
> > > inside the netcdf file, I need to download all the .nc files for suppose
> > > that have date values after 01/01/2015. Could you please help me writing
> > > that.
> > >
> > > Thanks.
> > > Sailesh.
> > >
> > >
> >
> > Ticket Details
> > ===================
> > Ticket ID: VKX-907984
> > Department: Support netCDF Java
> > Priority: Normal
> > Status: Open
> >
> >
> 
> 


Ticket Details
===================
Ticket ID: VKX-907984
Department: Support netCDF Java
Priority: Normal
Status: Open