RFR 8131029: JShell: recover from VMConnection launch failure

[Vicente-Arturo Romero-Zaldivar]

Looks good,

Vicente

On 06/01/2016 12:01 PM, Robert Field wrote:
> Please review --
>
> Attempt recovery from launch failure caused by either rare 
> intermittent JDI failures or bad configurations by using an 
> alternative connection and process-creation mechanism.
> Necessitated a clean-up of the JShell JDI code: removed JDIEnv which 
> provided no useful abstraction, coalescing the JDI connection 
> functionality in JDIConnection;
> remove unused and commented-out code from that class.
> Add a meta-ExecutionControl class, FailOverExecutionControl, which 
> cycles through ExecutionControl instances until one starts.
>
> Bug:
>     https://bugs.openjdk.java.net/browse/JDK-8131029
>
> Webrev:
>     http://cr.openjdk.java.net/~rfield/8131029v0.webrev/
>
> Thanks,
> Robert
>