According to its feature list "Quartz can run as a stand-alone program (within its own Java Virtual Machine), to be used via RMI".
I could not find any documentation how to start it in stand-alone mode, however.
"java -jar quartz.jar" does not do anything (there is not even a Main-Class specified in its mainfest).
All the examples in the distribution use Quartz as an embedded library.
So how does this work?