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[Alan Bateman]

Thanks for the update. So I'm curious how this worked previously, was 
this Maven plugin using its own class loader to load types from tools.jar?

-Alan


On 05/01/2015 16:55, Andrew Dinn wrote:
> Hi Alan/Rory,
>
> On 05/01/15 12:16, Alan Bateman wrote:
>>> . . .
>> If it's the JDK image then this should work as it's the equivalent of
>> pre jdk9-b41 with tools.jar on the class path. So I think you will have
>> to dig into, my only guess at this point is that TestNG is somehow
>> delegating to the extension class loader rather than the
>> system/application class loader.
> I have debugged this and the problem is indeed to do with faulty
> delegation - on the part of maven [naturlich :-]. Details are provided
> below. In summary, the problem can be fixed by configuring maven to stop
> dorking around with class loading. I'll be posting a new Byteman
> micro-release in the next week which can build and run correctly with
> all of JDK6/7/8/9. I'll announce details on this list when it is ready.
>
> regards,
>
> Andrew Dinn
> -----------
> Senior Principal Software Engineer
> Red Hat UK Ltd
> Registered in UK and Wales under Company Registration No. 3798903
> Directors: Michael Cunningham (USA), Matt Parson (USA), Charlie Peters
> (USA), Michael O'Neill (Ireland)
>
> ----- 8< -------- 8< -------- 8< -------- 8< -------- 8< -------- 8< ---
>
> The maven surefire plugin provides a boolean configuration property
> (childDelegation=true/false) which controls the behaviour of its loader
> implementation, class IsolatedClassLoader. The property configures
> loading to proceed either by normal parent delegation
> (childDelegation=true [sic]) or by means of a URL loader which first
> tries to use the bootstrap loader and then does a file lookup over  each
> path element of the classpath (childDelegation=false).
>
> [Yes, I know the property name is bizarrely counter-intuitive but then
> this is maven %-].
>
> Of course, being maven, it also defaults this configuration switch to
> false . . . which means that parent delegation as expected by the JDK9
> module setup is bypassed. This rather dirty maven trick works ok for
> Byteman using JDK 6, 7 and 8 because with those versions the pom
> finagles tools.jar into the classpath as a runtime dependency. Of
> course, with 9 I had to disable that dependency so parent delegation is
> the only way to get the missing classes. If the pom configures tests to
> be run with childDelegation=true then things still work ok.