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
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