[AURORA-560] Scheduler may hang while tearing down due to Quartz thread

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.5.0
• Component/s: Scheduler
• Assignee: Bill Farner
• Reporter: Bill Farner
• Created: 27/Jun/14 22:45
• Updated: 08/Jul/14 13:16
• Resolved: 03/Jul/14 18:50

Description

Noticed this in vagrant - scheduler is stuck tearing down, with this thread keeping it alive:

"aurora-cron-1_QuartzSchedulerThread" prio=10 tid=0x00007f215c98b000 nid=0x307a in Object.wait() [0x00007f21179b8000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
        at java.lang.Object.wait(Native Method)
        at org.quartz.core.QuartzSchedulerThread.run(QuartzSchedulerThread.java:253)
        - locked <0x00000000e131f170> (a java.lang.Object)

It turns out that construction of the Scheduler ends up creating and starting a non-daemon QuartzSchedulerThread within quartz code. We should be able to fix this by registering a shutdown hook upfront rather than doing so when we receive SchedulerActive.