How can I send a data array back and forth between java and python?
If the solution of writing/reading the numbers to a file somehow is not sufficient, you can try the following:
Instead of using Jython, you can use Pyro4 (and the Pyrolite client library for your java code) to call a running Python program from your java code.
This allows you to run your python code in a 'normal' python 3.6 interpreter for instance, rather than being limited to what version Jython is stuck on.
You'll have to launch the Python interpreter in a separate process though (but this could very well even be on a different machine)
I have a java program and I need it to get some data calculated by a python script. 
I've already got java to send an integer to python via jython's PythonInterpreter and displayed it, but I can't recover it to make other operations. Also, it would be great to send a full integer array rather than a single integer but I can't wrap my mind arround PyObjects and how to use them.
Is there any useful tutorial that covers arrays? I've been searching for a while but I just find integer and float related tutorials.