RFR 8023093: Add ManagementAgent.status diagnostic command

[Staffan Larsen]

Looks good! 

Thanks for splitting up the test file. This test has been known to be unstable - what platforms have you verified the changes on?

Thanks,
/Staffan
 
> On 27 mar 2015, at 17:29, Jaroslav Bachorik <jaroslav.bachorik at oracle.com> wrote:
> 
> Please, review the following change
> 
> Issue : https://bugs.openjdk.java.net/browse/JDK-8023093
> Webrev: http://cr.openjdk.java.net/~jbachorik/8023093/webrev.00 (hotspot, jdk)
> 
> This change adds a new 'ManagementAgent.status' diagnostic command. This command will output the current status of the management agent in the following format
> 
> ```
> Agent: <enabled|disabled>
> 
> (
>  ConnectionType: <local|remote>
>  Protocol: <rmi|...>
>  Host: <IP or host name>
>  URL: <valid JMX connector URL>
> 
>  (
>    Properties:
>    (
>      <propertyname>=<propertyvalue>
>    )+
>  )?
> )+
> ```
> 
> Where:
>  <name>    means an arbitrary value
>  |         means 'or'
>  ( and )   denote a block
>  +         block repeats one or more times
>  ?         block appears at most once
> 
> A new test is added exercising this diagnostic command. While adding the test I factored out the shared functionality from the JMXStartStopTest class and caused the changes in the test area to be a bit more extensive than just adding a new test class.
> 
> Thanks,
> 
> -JB-