Hi Christian,
I'm not experienced in the CIM but I dig a little and found some interesting articles.
In general I'm not sure the URL could be the right approach. You could try the WBEMClientFactory instead. The javax.wbem has a lot of tools to work exactly with CIM instances.
If you go this way, the client need to be initialized with the VcHostServiceTicket.sessionId as user and password.
I have found several articles posted within VMware's blogs about hardware monitoring via CIM. They all uses wbem implementations. Unfortunately the samples are in Pyton.
http://blogs.vmware.com/esxi/2010/04/hardware-health-monitoring-via-cim.html (above the title you will see links to the next part of this topic).
Sorry, for not being able to direct answer your question but hope the above links will help.
Regards,
--Martin
Martin Marinov
VMware Software Engineer
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