jScope fails because it cannot load the LocalDataProvider class

[mwinkel-dev]

Affiliation
DIII-D (filed on behalf of user Saeid H.)

Version(s) Affected
Client version: 7-139-59 (stable?)
Server version: ditto
Note: Omega has several MDSplus versions installed. It is unclear which version encountered the jScope error. (The module command is used to load a specific version, but there is also a default version.)

Platform(s)
The Omega server is running RHEL 8.8

Installation Method(s)
Installed by GA's CSS group

Describe the bug
When launching jScope, Java throws a ClassNotFound exception regarding mds.provider.LocalDataProvider. GA conjectures that this might be an environment variable issue associated with module definitions.

To Reproduce
Steps to reproduce the behavior:

1. TBD

Expected behavior
No exception thrown and jScope displays the desired data from the selected MDSplus trees.

Screenshots
n/a

Additional context
n/a

[mwinkel-dev]

jScope does work when using an mdsip connection to the Orion server (which is where the LHCD trees reside). The following screenshot was generated as follows:

• logged into Omega
• did not use the module command to load any specific environment
• used mdstcl to determine running MDSplus 7-139-59 (guessing it is stable and not alpha, but must check)
• at the Linux prompt,export lhcd_path=orion::
• jScope &
• from within jScope, loaded a previously created *.jscp configuration file

CORRECTION: This is actually using the local data provider class (as shown in the status bar of the screenshot). That is because the *.jscp file specified local. It surely means that jScope connected to mdsip on Omega, which then connected to Orion.

Scroll down four posts to see a screenshot of jScope directly connecting to Orion.

[mwinkel-dev]

jScope also worked with a local tree when the Network was set to local and a *.jscp file was loaded that referenced a simple tree containing fake data.

[mwinkel-dev]

However, a few days ago a LocalDataProvider error did occur with a developer build of alpha-7-157-1 on macOS Tahoe 26.2 (Apple Silicon CPU). This issue has not yet been investigated.

[mwinkel-dev]

More information is needed from the user in order to reproduce the jScope error that the user encountered on the Omega server.

Here is a list of questions. Post the answers to this GitHub issue.

• Are you using the module command to load a specific environment before running jScope?
• What MDSplus version is being used? Login to Omega and at the operating system prompt, type the following:

mdstcl
show version

• Is jScope attempting to access an MDSplus tree that is local to Omega? (Or is it instead attempting to access trees stored on GA's Atlas and/or Orion servers?)
• What is the tree name and shot number?
• What is the tree_path set to? (For example, if accessing a tree named, XYZ, then echo $xyz_path.)
• Was jScope's Networking menu used to select Local?

[mwinkel-dev]

These screenshots show the correct settings for jScope to directly connect to the Orion sever. (The port number has been obscured.)

However, it is conjectured that GA's servers are configured to use the MdsDataProviderLocal class (and not the MdsDataProvider class).