Did Java on Solaris once had a Fiber-like threads?

[Arkadiusz Gasiński]

Hi,

I recently found the "*JDK 1.1 for Solaris Developer's Guide*" article (
https://docs.oracle.com/cd/E19455-01/806-3461/6jck06gqe/index.html), which
says, in the Many-to-Many Model section, that "*a program can have as many
threads as are appropriate without making the process too heavy or
burdensome. In this model, a user-level threads library provides
sophisticated scheduling of user-level threads above kernel threads. The
kernel needs to manage only the threads that are currently active. A
many-to-many implementation at the user level reduces programming effort as
it lifts restrictions on the number of threads that can be effectively used
in an application.*"

That's just the definition of the many-to-many model, but later in the same
section, it's written that "*The Java on Solaris operating environment is
the first many-to-many commercial implementation of Java on an MT operating
system*". If that's the case, it looks like there already was a version of
Java that had Fiber-like threads. Was it only some proprietary
implementation just for Solaris? What happened to it?

BTW, if I understand correctly, the current versions of Open/Oracle JDK
employ the one-to-one multithreading models, correct?

Thanks,
Arek