I've found several posts with instructions of how to kill java thread with jdb http://www.rhcedan.com/2010/06/22/killing-a-java-thread/ or on SO. This works. Now I want to kill thread with Intellij-IDEA debugger. Is it possible to do?
There is a little icon on the right side of the Debug view:
This will open 'Threads' tab and there you can right-click on some of them and select 'Interrupt' (and press F9 if you are sleeping on some breakpoint).