8191846: jstat prints debug message when debugging is disabled

[Per Liden]

Thanks for reviewing Erik.

Erik pointer out to me off-line that we have additional jstat tests that 
where not covered by the hs-triers I ran, so I also ran the following 
tests and they all passed.

make run-test TEST=open/test/jdk/sun/tools/jstat
make run-test TEST=open/test/jdk/sun/tools/jstatd

/Per

On 2017-11-24 09:13, Erik Helin wrote:
> Hi Per,
>
> On 11/24/2017 09:01 AM, Per Liden wrote:
>> Hi,
>>
>> jstat is designed to handle the case where a perf counter doesn't
>> exits. In the output jstat will then print a "-" instead of the perf
>> counter value to indicate that the counter doesn't exist. However,
>> jstat also prints an unnecessary message, which clobbers the output.
>> This message might still be useful for debugging, but should only be
>> printed when jstat is running with debug messages enabled
>> (-J-DExpressionResolver.debug=true).
>>
>> Webrev: http://cr.openjdk.java.net/~pliden/8191846/webrev.0/
>
> I have limited experience of jstat (I have only contributed two patches
> to jstat), but this looks good as far as I can see.
>
> Thanks,
> Erik
>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8191846
>> Testing: hs-tier1, hs-tier2
>>
>> /Per