From: https://github.com/openjdk/jmc/pull/548#issuecomment-1929038577

https://github.com/openjdk/jmc/blob/master/application/org.openjdk.jmc.rjmx.ext/META-INF/services/javax.management.remote.JMXConnectorProvider is not detected by javax.management.remote.JMXConnectorFactory' s classloader.
I also tried to use org.openjdk.jmc.rjmx.common.internal.RJMXConnection 's classloader, but that no longer works as the .ext module is not visible from rjmx.common .

Bottom line seems to me that the JMX protocol extension mechanism no longer works in JMC 9

This bug occurred after the migration of rjmx code from application to core, with the issue being summarized quite well by the above comment that rjmx.ext is not visible by the newly moved rjmx.common.

Previously rjmx.ext manifest had a "Fragment-Host: org.openjdk.jmc.rjmx", which is what allowed this mechanism to work. However, now the relevant code is in rjmx.common so the rjmx.ext MANIFEST.mf needs to be updated to point there instead.

I've verified that once this change is made the OsgiServicesJmxProviderProxy and EclipseJmxProviderProxy are operational again.