Java Development Initiative Status Report
October 07, 2002
This report updates the status of Unidata's Java development
efforts reported at the last Policy
The long-term objectives of Unidata's Java Development Initiative are:
- Deliver turn-key platform-independent applications for the
analysis and visualization of meteorological data. These
applications must provide and extend the most important capabilities
of currently-available applications such as GEMPAK, GARP, and
McIDAS. Use of these applications should require no knowledge
of Java or component architectures.
- Deliver easily installed executables, user documentation, and
test cases for the turn-key applications.
- Identify or create a component-oriented framework that supports
construction of custom applications from components used to
build the turn-key applications. This framework should be
useful to create new combinations of components that provide
subsets of the capabilities of the turn-key applications,
connect them in unanticipated ways, or provide tailored
mini-applications for embedding in educational materials. Use
of these components may require knowledge of component
architectures or Java.
- Deliver full source code, class documentation, and test cases
for the MetApps components.
- Enlist other developers in enhancing components and developing
new components for the framework by providing an
archive, mailing list, developers' forums, documentation, web
site, and support for the components.
To accomplish these long-term goals, short-term objectives include the
delivery of incremental releases involving users, incorporating
feedback, refining the development process, and enhancing the software
with each release.
Progress to Date
Four prototype MetApps applications have been developed: a gridded
data viewer for viewing model data, an interactive sounding application,
an image viewer for viewing and looping image data from local and
remote datasets, and a surface observations viewer. Development on all
these prototypes as standalone applications has ceased. Lessons learned
in developing these prototypes and some of the components have been
incorporated into the development of an Integrated Data Viewer (IDV)
application which will be the reference application for goals #1 and #2
listed above. All work since the last status report has focused on the
development of the IDV. This application is being used to develop and
test the framework listed in goal #3 above. A developer's manual is in
progress to satisfy goal #5.
In more detail, recent accomplishments include:
- A major milestone in the MetApps project was achieved on September 4,
2002 with the first public beta release of the Integrated Data Viewer
(IDV) version 1.0. This release allows users to integrate and work
with grids, satellite and radar imagery, surface and upper air
data and HTML documents in a common interface. The IDV can be downloaded at
http://www.unidata.ucar.edu/software/metapps/. This release does
not signal the completion of the project nor the attainment of all the
goals, but the IDV is at a point where it can be generally useful.
The release to a wider audience will be used to garner community input
for further development. A similar strategy was employed in the GARP
- A customized version of the IDV was made available to ATD scientists
in the field during the IHOP project. This was developed with
input from IHOP science personnel (Tammy Weckwerth and Jim Wilson).
Much of the work to integrate the customized features (custom User
Interface (UI), special data access methods, customized station tables,
realtime and archived airplane tracks, customized maps, support
for 3D gridded radar datasets from SPOL and NEXRAD stations, imagery
in netCDF format, and an enhanced Skew-T component for displaying
mobile GLASS soundings as well as model soundings)
benefits the general IDV user community by creating a more flexible
framework for creating custom applications. From the Unidata
perspective, the use of IDV in IHOP was a bit premature. Many of
the features that would have been useful were not well tested and
there were severe performance issues. A followup meeting with the
IHOP scientists brought to light several issues that need to be
- Performance - this was the major complaint about the IDV. We
will work with ATD to compare IDV performance against other software
available to the scientists (e.g. Zebra).
- Unfamiliarity with the IDV - for future projects, scientists
need to have access to and training on new software before they
can use it effectively. In general, they went with what they
were familiar with (Zebra) if they couldn't figure out how to do
it in IDV. We will work with Tammy on using the IDV for post-
project analysis of the data gathered during IHOP.
- Support for other data types - there were several datasets
(MM5 output, FSL gridded data, OK Mesonet) that were not viewable
with the IDV. We will investigate the feasability of
incorporating these data during the post-project analysis. ATD
staff will need to do the work on data adapter for special
datasets (e.g. SPOL sweepfiles).
- Collaboration has continued with NCAR/SCD on the continued development
of the Visual Geophysical Exploration Environment (VGEE) using the
IDV framework. This provides us with another way to test and improve
the framework for people creating custom applications. Rajul Pandya,
who used the VGEE-IDV at Westchester University of PA is now working
for DLESE/Unidata. As part of his work as the THREDDS liason, we
are working together to move the VGEE datasets into THREDDS catalogs
which can be indexed in DLESE. Rajul will work with the MetApps
developers to enhance the VGEE curriculum materials to take advantage
of the IDV's flexible configuration and HTML interface. Papers on this
work will be presented at the AGU Fall Meeting and the AMS IIPS meeting
- The IDV and THREDDS development groups have been working closely
recently to define the needs of IDV as a THREDDS client. This effort
includes developing THREDDS capability servers which can be queried
for effective access to data and to provide user interface (UI)
definitions based on XML. A web-browser or Java client like IDV
could use this XML to generate a UI on the fly for accessing the
data on the THREDDS server.
- A group at RAP is looking for a general netCDF browsing/viewing program.
They were given a demonstration of the IDV and found that many of the
features they need are in the IDV. We will be working with them
on netCDF conventions for their files and ingesting and working
with their data in the IDV. One of the datasets they want to
view is the netCDF METAR data from the metar2nc decoder program
from Unidata. The IDV needs to read these files for the general
community and work has begun on that. These files are similar to
the AWIPS netCDF METAR files. Jim Cowie is the contact for that
- We have been working with Capt. Richard Gonzales at the Air
Force Institute of Technology (AFIT) on using a freely available
Java GRIB reader (JGrib)
to directly ingest GRIB data into the
IDV. Capt. Gonazales wants to use the IDV for his work on the
Laser System. This would be a benefit to the community as GRIB
is one of the formats that users have requested for data read by
the IDV (e.g. from COMET case studies). Capt. Gonzales will contribute
his code to Unidata.
- With the release of the IDV and the most intense phase of
development over, there have been a couple of re-assignments from the
MetApps group to assist other areas in Unidata. Steve Emmerson is now
working on LDM 5.X development and support to fill that need. Stu Wier
has been designated as the primary IDV support contact. Jeff McWhirter
is assisting in the development of the new Unidata Web Site, but his
primary role is still IDV development. Don Murray continues as the
technical lead on the project.
Current development beyond what's listed above includes:
Ongoing efforts include:
- Incorporation of radar data in Level II Archive Format into the IDV by
the AGU Fall meeting.
- Incorporation of netCDF METAR data in AWIPS and metar2nc formats and
an interface for creating customized station model configurations.
- Display sounding winds on SkewT and in 3D hodograph.
- Addition of a drawing/annotation tool.
- Use THREDDS capability server work to develop a cohesive framework
for accessing local and remote datasets. This includes the
ability to save off time relative (i.e. latest data instead
of absolute times) pointers to datasets.
- Performance enhancements and comparisons with other tools
(Zebra, McIDAS, GEMPAK).
- Enhancement of derived quantities and formulas portion of IDV.
- Collaborating in the development of
- Keeping up with new Java interfaces and developments
- Various and sundry IDV bug fixes and enhancements.
This document is maintained by
Don Murray <firstname.lastname@example.org>