I am newbie to Kubernetes, and I need to add some rules to the network policy:
I found some documents, but I couldn't find for internet.
And finally, how can I write this policy with Kubernetes java library?
Kubernetes Network Policy is designed to restrict access inside the cluster, limiting access from pods to another pods and services.
If you need to restrict access from/to internet, it's better to use cloud provider capabilities or a physical device like:
To manage Kubernetes from java code you can use official java client library.