Re: inspect a thread’s stack

[Martin Skarsaune]

Hi Pietro

Not sure JDI is what you really want, but if you would like to play with it
I have some code here that uses the PID of the JVM to open a connection to
itself and among other things print stack frames with variables:

https://github.com/skarsaune/kantega.debug and some demo here:
https://www.youtube.com/watch?v=5sXxIfjaALg

So an example of what you can do, but not suitable for anything serious.

For inspecting the stack, there is an cool reflection hack to the Java 9
API demonstrated by Andrei Pangin here that is able to capture stack
values: https://vimeo.com/233820012

For serious work I suppose an JVMTI agent is the best option. Others are in
a better position to offer guidance on that.

Martin



fre. 6. apr. 2018 kl. 18:14 skrev Pietro Paolini <
Pietro.Paolini at alfasystems.com>:

> Hi all,
>
>
>
> I apologise if this is not the right ML for it but  I couldn’t find
> exactly what I was looking for when Googling the problem. I am a bit new to
> the JDI world.
>
>
>
> I would like to inspect the stack-frame of a specific  thread, I came
> across the StackFrame/ThreadReference classes but I couldn’t find a way
> examples where their usage is shown
>
> without connecting to the VM somehow, like a debugger would do.
>
>
>
> Is it possible to
>
>
>
> inspect a thread’s stack “locally”  ? In my mind I could be able to have a
> function such as :
>
>
>
> static void hook(Thread thread) {
>
>
>
> thread.wait() // stop that thread
>
>
>
> // inspect the frames of that thread doing any needed business with them
>
> }
>
>
>
> I’d need this for diagnostic purposes of my application.
>
>
>
> Thanks,
>
> Pietro
>
>
>
>
>
>
> Pietro Paolini
> Consultant
>
> Alfa
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