Communication between Plug Ins

Andreas Gerum Sep 01, 2016

Hi
I´m trying to develop a JIRA - Plugin which needs data from another plugin(Kanoah). I tried to follow the examples in "JIRA 5.x Development Cookbook" but they dont work with JIRA 7.x. So my questions are :
Is REST the only way for plug-ins to communicate with each other ?
Does someone know a link with code example , concering communication between plug ins?
If REST is the only way, how could https be used here?
How has REST access canged since JIRA 5?
I hope someone could help me with this matter.
best regards.