Nujan: A pure Java HDF5 and NetCDF4 writer

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
  - Nujan does not depend on any C code, so does not use the JNI
    (Java Native Interface)
  - Nujan supports a wide set of HDF5 features, but not all.
    Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html

For questions and comments contact ...

Steve Sullivan steves@ucar.edu

···

--
Steve Sullivan steves@ucar.edu 303-497-2823

FL/2, Research Applications Laboratory
National Center for Atmospheric Research
PO Box 3000
Boulder CO 80307
USA

This sounds pretty interesting for us .NET types, as through the frightening brilliance of IKVM.NET, we can run "pure" Java code as "pure" .NET code.

Are there any plans for or related libraries that can read similar simple datasets (2D & 3D arrays of floats)? An advantage, I would imagine, to doing this in "pure" Java is that it would be more likely to be threadsafe.

Cheers,

Sebastian

···

On Sep 9, 2010, at 4:54 PM, Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
- Nujan does not depend on any C code, so does not use the JNI
   (Java Native Interface)
- Nujan supports a wide set of HDF5 features, but not all.
   Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html

For questions and comments contact ...

Steve Sullivan steves@ucar.edu

--
Steve Sullivan steves@ucar.edu 303-497-2823

FL/2, Research Applications Laboratory
National Center for Atmospheric Research
PO Box 3000
Boulder CO 80307
USA

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
  - Nujan does not depend on any C code, so does not use the JNI
    (Java Native Interface)
  - Nujan supports a wide set of HDF5 features, but not all.
    Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html
  

Hi Steve,

    It's not clear from the site if it is the design goals of Nujan to eventually be HDF5 feature complete?

    I can understand that it is currently not and may not be for some time but am keen to find out the Nujan's long term goals.

Regards

Hi Steve,
  Very cool, congrats on getting this out the door!

    Quincey

···

On Sep 9, 2010, at 11:54 PM, Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
- Nujan does not depend on any C code, so does not use the JNI
   (Java Native Interface)
- Nujan supports a wide set of HDF5 features, but not all.
   Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html

For questions and comments contact ...

Steve Sullivan steves@ucar.edu

--
Steve Sullivan steves@ucar.edu 303-497-2823

FL/2, Research Applications Laboratory
National Center for Atmospheric Research
PO Box 3000
Boulder CO 80307
USA

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

Nicholas,

Currently we do plan to continue work on Nujan, but exactly which
features get implemented is not yet known. A lot depends on the
needs of our primary customer, an FAA project. Also if many
users request a certain feature, we may be able to implement it.
As usual, funding will be a determining factor.

Steve

···

On Fri, Sep 10, 2010 at 10:59:58AM +1000, Nicholas Yue wrote:

Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
  - Nujan does not depend on any C code, so does not use the JNI
    (Java Native Interface)
  - Nujan supports a wide set of HDF5 features, but not all.
    Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html
  

Hi Steve,

   It's not clear from the site if it is the design goals of Nujan to
eventually be HDF5 feature complete?

   I can understand that it is currently not and may not be for some
time but am keen to find out the Nujan's long term goals.

Regards

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

--
Steve Sullivan steves@ucar.edu 303-497-2823

FL/2, Research Applications Laboratory
National Center for Atmospheric Research
PO Box 3000
Boulder CO 80307
USA

Sebastian,

Part of that already exists. The NetCDF java library,
http://www.unidata.ucar.edu/software/netcdf-java/ is pure Java
and can read some types of HDF5 files and present them via a
NetCDF4 API.

Aside from that I know of no plans to make an HDF5 pure Java
reader.

Steve

···

On Thu, Sep 09, 2010 at 08:15:31PM -0500, Sebastian Good wrote:

This sounds pretty interesting for us .NET types, as through the frightening brilliance of IKVM.NET, we can run "pure" Java code as "pure" .NET code.

Are there any plans for or related libraries that can read similar simple datasets (2D & 3D arrays of floats)? An advantage, I would imagine, to doing this in "pure" Java is that it would be more likely to be threadsafe.

Cheers,

Sebastian

On Sep 9, 2010, at 4:54 PM, Steve Sullivan wrote:

> UCAR is releasing a beta version of Nujan, a pure Java writer for
> HDF5 and NetCDF4 files. Nujan is 100% open source and is
> released under the MIT license.
>
> Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
> and NetCDF4 files compatible with NetCDF 4.1.1 and later.
>
> The primary differences between Nujan and the existing
> HDF5 Java writer are:
> - Nujan does not depend on any C code, so does not use the JNI
> (Java Native Interface)
> - Nujan supports a wide set of HDF5 features, but not all.
> Details are on the web page.
>
> Details and download are at:
> http://www.ral.ucar.edu/~steves/nujan.html
>
> For questions and comments contact ...
>
> Steve Sullivan steves@ucar.edu
>
>
> --
> Steve Sullivan steves@ucar.edu 303-497-2823
>
> FL/2, Research Applications Laboratory
> National Center for Atmospheric Research
> PO Box 3000
> Boulder CO 80307
> USA
>
>
> _______________________________________________
> Hdf-forum is for HDF software users discussion.
> Hdf-forum@hdfgroup.org
> http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

--
Steve Sullivan steves@ucar.edu 303-497-2823

FL/2, Research Applications Laboratory
National Center for Atmospheric Research
PO Box 3000
Boulder CO 80307
USA

Werner,

Using a network interface is not possible with this API.
It does not write the file sequentially. For example, the
file length is computed after writing all the data, and the
the API then writes the file length into the file header.

Steve

···

On Fri, Sep 10, 2010 at 09:49:16AM +0200, Werner Benger wrote:

Steve,

does or will the pure Java HDF5 support writing a file image to a TCP/IP
socket instead of a file? In HDF5 this is possible through the virtual
file drivers, I'd imagine that using sockets would be even easier in Java
than in C, and could be a nice feature to stream an HDF5 file from a
Java VM through the network or another application.

  Werner

On Fri, 10 Sep 2010 05:23:46 +0200, Steve Sullivan <steves@ucar.edu> wrote:

Nicholas,

Currently we do plan to continue work on Nujan, but exactly which
features get implemented is not yet known. A lot depends on the
needs of our primary customer, an FAA project. Also if many
users request a certain feature, we may be able to implement it.
As usual, funding will be a determining factor.

Steve

On Fri, Sep 10, 2010 at 10:59:58AM +1000, Nicholas Yue wrote:

Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
  - Nujan does not depend on any C code, so does not use the JNI
    (Java Native Interface)
  - Nujan supports a wide set of HDF5 features, but not all.
    Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html

Hi Steve,

   It's not clear from the site if it is the design goals of Nujan to
eventually be HDF5 feature complete?

   I can understand that it is currently not and may not be for some
time but am keen to find out the Nujan's long term goals.

Regards

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

--
___________________________________________________________________________
Dr. Werner Benger Visualization Research
Laboratory for Creative Arts and Technology (LCAT)
Center for Computation & Technology at Louisiana State University (CCT/LSU)
211 Johnston Hall, Baton Rouge, Louisiana 70803
Tel.: +1 225 578 4809 Fax.: +1 225 578-5362

--
Steve Sullivan steves@ucar.edu 303-497-2823

FL/2, Research Applications Laboratory
National Center for Atmospheric Research
PO Box 3000
Boulder CO 80307
USA

Steve,

  does or will the pure Java HDF5 support writing a file image to a TCP/IP
socket instead of a file? In HDF5 this is possible through the virtual
file drivers, I'd imagine that using sockets would be even easier in Java
than in C, and could be a nice feature to stream an HDF5 file from a
Java VM through the network or another application.

  Werner

···

On Fri, 10 Sep 2010 05:23:46 +0200, Steve Sullivan <steves@ucar.edu> wrote:

Nicholas,

Currently we do plan to continue work on Nujan, but exactly which
features get implemented is not yet known. A lot depends on the
needs of our primary customer, an FAA project. Also if many
users request a certain feature, we may be able to implement it.
As usual, funding will be a determining factor.

Steve

On Fri, Sep 10, 2010 at 10:59:58AM +1000, Nicholas Yue wrote:

Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
  - Nujan does not depend on any C code, so does not use the JNI
    (Java Native Interface)
  - Nujan supports a wide set of HDF5 features, but not all.
    Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html

Hi Steve,

   It's not clear from the site if it is the design goals of Nujan to
eventually be HDF5 feature complete?

   I can understand that it is currently not and may not be for some
time but am keen to find out the Nujan's long term goals.

Regards

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

--
___________________________________________________________________________
Dr. Werner Benger Visualization Research
Laboratory for Creative Arts and Technology (LCAT)
Center for Computation & Technology at Louisiana State University (CCT/LSU)
211 Johnston Hall, Baton Rouge, Louisiana 70803
Tel.: +1 225 578 4809 Fax.: +1 225 578-5362

Steve,

  the same would be the case with the C library, which would first build
an HDF5 image in memory and stream the complete image once the file is closed
and the length is known and fixed.
  Of course, this approach only works as long as the HDF5 file fits into
memory, larger files would need to be split into smaller ones.

  Werner

···

On Fri, 10 Sep 2010 14:37:43 +0200, Steve Sullivan <steves@ucar.edu> wrote:

Werner,

Using a network interface is not possible with this API.
It does not write the file sequentially. For example, the
file length is computed after writing all the data, and the
the API then writes the file length into the file header.

Steve

On Fri, Sep 10, 2010 at 09:49:16AM +0200, Werner Benger wrote:

Steve,

does or will the pure Java HDF5 support writing a file image to a TCP/IP
socket instead of a file? In HDF5 this is possible through the virtual
file drivers, I'd imagine that using sockets would be even easier in Java
than in C, and could be a nice feature to stream an HDF5 file from a
Java VM through the network or another application.

  Werner

On Fri, 10 Sep 2010 05:23:46 +0200, Steve Sullivan <steves@ucar.edu> wrote:

Nicholas,

Currently we do plan to continue work on Nujan, but exactly which
features get implemented is not yet known. A lot depends on the
needs of our primary customer, an FAA project. Also if many
users request a certain feature, we may be able to implement it.
As usual, funding will be a determining factor.

Steve

On Fri, Sep 10, 2010 at 10:59:58AM +1000, Nicholas Yue wrote:

Steve Sullivan wrote:

UCAR is releasing a beta version of Nujan, a pure Java writer for
HDF5 and NetCDF4 files. Nujan is 100% open source and is
released under the MIT license.

Nujan creates HDF5 files compatible with HDF5 1.8.5 and later,
and NetCDF4 files compatible with NetCDF 4.1.1 and later.

The primary differences between Nujan and the existing
HDF5 Java writer are:
  - Nujan does not depend on any C code, so does not use the JNI
    (Java Native Interface)
  - Nujan supports a wide set of HDF5 features, but not all.
    Details are on the web page.

Details and download are at:
http://www.ral.ucar.edu/~steves/nujan.html

Hi Steve,

   It's not clear from the site if it is the design goals of Nujan to
eventually be HDF5 feature complete?

   I can understand that it is currently not and may not be for some
time but am keen to find out the Nujan's long term goals.

Regards

_______________________________________________
Hdf-forum is for HDF software users discussion.
Hdf-forum@hdfgroup.org
http://mail.hdfgroup.org/mailman/listinfo/hdf-forum_hdfgroup.org

--
___________________________________________________________________________
Dr. Werner Benger Visualization Research
Laboratory for Creative Arts and Technology (LCAT)
Center for Computation & Technology at Louisiana State University (CCT/LSU)
211 Johnston Hall, Baton Rouge, Louisiana 70803
Tel.: +1 225 578 4809 Fax.: +1 225 578-5362

--
___________________________________________________________________________
Dr. Werner Benger Visualization Research
Laboratory for Creative Arts and Technology (LCAT)
Center for Computation & Technology at Louisiana State University (CCT/LSU)
211 Johnston Hall, Baton Rouge, Louisiana 70803
Tel.: +1 225 578 4809 Fax.: +1 225 578-5362