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[netCDFJava #WHR-919836]: Problem reading grib2 files in memory

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  • Subject: [netCDFJava #WHR-919836]: Problem reading grib2 files in memory
  • Date: Fri, 15 Mar 2013 15:48:59 -0600
Hi Adrian,

Thank you for bringing this issue to our attention.  We believe we have 
implemented a solution in our latest release (4.3.16), though it is not tested, 
and we would appreciate your feedback on it.  Note that, due to the nature of 
grib files and their associated tables (as opposed to a self-contained dataset 
such as NetCDF), the netcdf-java code will still need to maintain ncx and gbx9 
files on disk.

Cheers,
  Lansing Madry
  Unidata
  Boulder, Colorado

> Hi,
> 
> I have run into a bug while trying to read a grib2 files from a byte
> array.
> 
> I am trying to use the static method
> NetcdfFile openInMemory(String name, byte[] data)
> 
> But the Grib2Iosp clas is calling the makeIndex method in the Grib2Index
> cl= ass which is using the location to try and open a RandomAccessFile
> using th= e filename.  It seems the Grib2Index class is written based
> on files on dis= k and does not support data in memory.
> 
> This all fails in a heap since there isn't a file on disk.
> 
> Here is the stack trace I'm getting:
> Exception in thread "main" java.io.FileNotFoundException: test-file (The 
> system cannot find the file specified)
> at java.io.RandomAccessFile.open(Native Method)
> at java.io.RandomAccessFile.<init>(RandomAccessFile.java:233)
> at java.io.RandomAccessFile.<init>(RandomAccessFile.java:118)
> at ucar.unidata.io.RandomAccessFile.<init>(RandomAccessFile.java:277)
> at ucar.unidata.io.RandomAccessFile.<init>(RandomAccessFile.java:259)
> at ucar.nc2.grib.grib2.Grib2Index.makeIndex(Grib2Index.java:234)
> at 
> ucar.nc2.grib.GribIndex.makeGribCollectionFromSingleFile(GribIndex.java:112)
> at ucar.nc2.grib.grib2.Grib2Iosp.open(Grib2Iosp.java:310)
> at ucar.nc2.NetcdfFile.<init>(NetcdfFile.java:1499)
> at ucar.nc2.NetcdfFile.open(NetcdfFile.java:887)
> at ucar.nc2.NetcdfFile.openInMemory(NetcdfFile.java:793)
> at griberror.TestGribReading.main(TestGribReading.java:22)
> 
> Cheers
> 
> Adrian Jarvis
> Senior Java Developer,
> MetService New Zealand Ltd
> 
> 
> 


Ticket Details
===================
Ticket ID: WHR-919836
Department: Support netCDF Java
Priority: High
Status: Open