How to check if a thread is a daemon thread in the IntelliJ IDEA debugger?

Question

I am troubleshooting a JOGL application shutdown. As the application is not terminating properly, I would like to know which of the threads is causing this. Is there a way to check in the debugger which threads are non-daemon ones?

If there is nothing in the IDE for this, is there some other way to check for this, perhaps some clever expression I could enter as a watch expression to list the non-deamon threads?

Note: an issue exists to add the support into the debugger: https://youtrack.jetbrains.com/issue/IDEA-132042 — Suma, Dec 05 '18 at 11:42

score 3 · Accepted Answer · answered Dec 05 '18 at 10:41

3

If you can put break point you can use call Evaluate expression (Alt + F8) and type Thread.getThreads() the you can inspect every thread if it's deamon.

answered Dec 05 '18 at 10:41

Ulad

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3

Or you can evaluate `Thread.currentThread().isDeamon()` when you breakpoint a specific thread. – Peter Lawrey Dec 05 '18 at 12:22

score 1 · Answer 2 · answered Aug 14 '20 at 04:30

Right click on a stack frame and click "Export Treads...". It will create a text description of every thread and their stack and stuff but most importantly the daemon threads will say "daemon" next to them.

"RMI Scheduler(0)@4275" daemon prio=5 tid=0x14 nid=NA waiting
  java.lang.Thread.State: WAITING
      at jdk.internal.misc.Unsafe.park(Unsafe.java:-1)
      at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:234)
...

How to check if a thread is a daemon thread in the IntelliJ IDEA debugger?

2 Answers2