function attr=nj_attget(uri,var)
% NJ_ATTGET get attributes for NetCDF file, NetCDF URL or OpenDAP URL
% Usage:    attr=nj_attget(file,var);
%   where:  ncfile = local file name or a URL 
%           var  = variable     
%
%           [attr]= nj_attget(uri);
%           Returns only 'global' attributes associated with the netcdf
%           file. 

%           [attr]=nj_attget(uri,'temp'); % get attributes for
%           variable 'temp', as well as global attributes associated with
%           the nc file.
%           attr.var = variable attributes
%           attr.global = global attributes
%         
%  
% skbhate@ngi.msstate.edu
%
% import the NetCDF-Java methods 
import msstate.cstm.data.JDataset
import msstate.cstm.data.grid.JGeoGridDataset

if nargin < 1 
    disp('Check input arguments!')
    help nj_attget
    return
end

try 
    % open CF-compliant NetCDF File as a Common Data Model (CDM) "Grid Dataset"
        GridData = JDataset(uri);
        %associated geo grid 
        gds = GridData.getGridDataset();
      
        
   switch nargin
      case 1       
        globalattr=gds.getGlobalAttributes().toArray();
        attr = globalattr; 
      case 2 
        GeoGridData = JGeoGridDataset(gds,var); 
        globalattr = gds.getGlobalAttributes().toArray();
        varattr = GeoGridData.getGeoGrid.getAttributes().toArray(); % variable attributes
        attr.global = globalattr;
        attr.var = varattr;
      otherwise, error('MATLAB:cf_attget:Nargin',...
                        'Incorrect number of arguments'); 
   end
   

    %cleanup
    GridData.close();
    
catch 
    %gets the last error generated 
    err = lasterror();    
    disp(err.message); 
end