RFR: JDK-8180709: java -javaagent:agent.jar with run-time that does not contain java.instrument prints confusing error

[Kirk Pepperdine]

Hi,

> On Dec 18, 2017, at 9:11 PM, gary.adams at oracle.com wrote:
> 
> The only legitimate reason libinstrument would be missing is if java.instrument was not included.
> Any other speculation about why libinstrument was not found is hard to explain. e.g. until
> the vm is initialized we can not explicitly say whether java.instrument module is present or not.

This is the only legitimate reason that is imaginable. I’d suggest that rather than overreaching you just state what you tried to do and that it failed.

Kind regards,
Kirk Pepperdine

> 
> 
> On 12/18/17 2:39 PM, Chris Plummer wrote:
>> Hi Gary,
>> 
>> Overall looks good. There's one minor change you might wanted to consider. It's possible the library failed to load for reasons other than java.instrument not being included. I see the error output already includes the error message from the failed dll_open() call, so why not just suggest that it *may* be due to java.instrument missing rather than implying that is known to be the reason why.
>> 
>> thanks,
>> 
>> Chris
>> 
>> On 12/18/17 6:38 AM, Gary Adams wrote:
>>> Here's a simple fix to include additional information when the instrument library is
>>> missing from the jre and the command line requests -javaagent.
>>> 
>>>  Issue: https://bugs.openjdk.java.net/browse/JDK-8180709
>>>  Webrev: http://cr.openjdk.java.net/~gadams/8180709/webrev.00/
>>> 
>>> 
>> 
>> 
>