Product Version = NetBeans IDE Dev (Build 201202190400)
Operating System = Windows 7 version 6.1 running on x86
Java; VM; Vendor = 1.6.0_25
Runtime = Java HotSpot(TM) Client VM 20.0-b11

Was implementing an object constructor that called it's parent object's constructor.
I typed "parent", then using the keyboard arrows selected "parent::__construct()" from the autocomplete box and then hit Enter.
The UI froze and Netbean's idled at 27% CPU usage for at least 10 minutes whilst my CPU temp rose to 72C before I killed it from Task Manager.
Repeated the process and got exactly the same behaviour.

class Segment extends Conditions {
		
    private $segment;
		
    function Segment() {
        parent::__construct();
    }
}