PING: RFR: JDK-8151815: Could not parse core image with JSnap.

[Dmitry Samersoff]

Yasumasa,

1. It's better to change JSnap code to produce meaningful error message
instead of NPE.

2. We should check that no other consumer of perf counters rely on the
fact it's NULL after call to destroy(). I'm not sure that this part of
the fix is not dangerous.

-Dmitry

On 2016-03-29 15:02, Yasumasa Suenaga wrote:
> PING: Could you review it?
> 
> 
> Yasumasa
> 
> 
> On 2016/03/22 21:24, Yasumasa Suenaga wrote:
>> PING: Could you review it?
>>
>> Yasumasa
>>
>> 2016/03/14 23:39 "Yasumasa Suenaga" <yasuenag at gmail.com
>> <mailto:yasuenag at gmail.com>>:
>>
>>     Hi all,
>>
>>     When I use `jhsdb jsnap` to get PerfCounter from core images, I
>> encountered NPE:
>>     -------------
>>     Exception in thread "main" java.lang.NullPointerException
>>              at sun.jvm.hotspot.tools.JSnap.run(JSnap.java:45)
>>              at sun.jvm.hotspot.tools.Tool.startInternal(Tool.java:260)
>>              at sun.jvm.hotspot.tools.Tool.start(Tool.java:223)
>>              at sun.jvm.hotspot.tools.Tool.execute(Tool.java:118)
>>              at sun.jvm.hotspot.tools.JSnap.main(JSnap.java:67)
>>              at sun.jvm.hotspot.SALauncher.runJSNAP(SALauncher.java:352)
>>              at sun.jvm.hotspot.SALauncher.main(SALauncher.java:404)
>>     -------------
>>
>>     PerfMemory::destroy() clears all members which are used in JSnap.
>>     Thus NPE is occurred.
>>
>>     I uploaded webrev for this issue.
>>     Could you review it?
>>
>>     http://cr.openjdk.java.net/~ysuenaga/JDK-8151815/webrev.00/
>>
>>     I cannot access JPRT.
>>     So I need a Sponsor.
>>
>>
>>     Thanks,
>>
>>     Yasumasa
>>


-- 
Dmitry Samersoff
Oracle Java development team, Saint Petersburg, Russia
* I would love to change the world, but they won't give me the source code.