8205132: Remove Thread.countStackFrames()

[Mandy Chung]

On 10/29/19 9:26 AM, Alan Bateman wrote:
> On 23/10/2019 08:25, Alan Bateman wrote:
>>
>> Thread::countStackFrames has been deprecated for 20+ years and has 
>> been marked for-removal since Java SE 9. I'd like to remove it for 
>> Java SE 14. It's was never a well-defined method and I've been unable 
>> to find anything that uses it. The StackWalker API is a much better 
>> solution for code that is interested in the number of stack frames.
> Joe Darcy has suggested degrading the method in advance of its 
> removal. We did the same with stop(Throwable) when we changed it to 
> throw UOE in Java SE 8 before finally removing it in 11. Here is the 
> updated webrev and CSR. The CSR will need to be re-reviewed. The 
> method description is brief and the same as what we did for 
> stop(Throwable).
>
> http://cr.openjdk.java.net/~alanb/8205132/webrev.02/
>
> https://bugs.openjdk.java.net/browse/JDK-8232654
>

Both look good.

> Also just to summarize the discussion/objection from Seth Lytle. I 
> think we've established that that it was a regression in JDK 10 that 
> allowed that example to work. The method has always been specified to 
> fail when the thread is not suspended.

Good find and I agree it's a regression.

Mandy