Get Max no of Threads allowed by OS

Is there a way in java to programatically get the maximum number of threads that are allowed to be created by an operating system?
Thru my readings on forums, I gather that though there is no such limit for green-type of java threads (I am not sure what green-type means), other regular threads are bound by the max thread limit allowed by the kernel. Is there a way to programmtically get this limit?
If there is no such API to get this information in Java directly, is there some command that can be invoked using the Runtim.exec() methods depending upon the OS type?
Thank you

It depends probably on the OS, the mem size, the number and type of CPUs... in short: Java isn't really supposed to care.
There is no way, and IMO there also isn't really a need to know.

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