Proposal:JdpController.getProcessId() VM compatibility improvement

[Alan Bateman]

This seems a good clean-up, esp. as java.management doesn't open 
sun.management to jdk.management.agent so I'll bet this wasn't working 
any. I assume the exception swallowing can be removed too.

Can you bring this to serviceability-dev as this is where this code is 
maintained?

On 22/06/2017 14:34, Andrew Leonard wrote:
> Hello,
> I would like to propose the change below to the
> JdpController.getProcessId() method which currently uses a reflection hack
> and the VMManagement interface. Instead for JDK9+ we can use the
> ProcessHandle.current().getPid() method, which will also allow better
> compatibility with other pluggable VMs.
>
> jdk/src/jdk.management.agent/share/classes/sun/management/jdp/JdpController.java
> 36d35
> < import sun.management.VMManagement;
> 137,146c136,137
> <             // Get the current process id using a reflection hack
> <             RuntimeMXBean runtime =
> ManagementFactory.getRuntimeMXBean();
> <             Field jvm = runtime.getClass().getDeclaredField("jvm");
> <             jvm.setAccessible(true);
> <
> <             VMManagement mgmt = (sun.management.VMManagement)
> jvm.get(runtime);
> <             Method pid_method =
> mgmt.getClass().getDeclaredMethod("getProcessId");
> <             pid_method.setAccessible(true);
> <             Integer pid = (Integer) pid_method.invoke(mgmt);
> <             return pid;
> ---
>>              // Get the current process id
>>              return (int)ProcessHandle.current().getPid();
> I'd appreciate any feedback please, and how I would go about obtaining a
> sponsor and contributor?
>
> Thanks
> Andrew
>
> Andrew Leonard
> Java Runtimes Development
> IBM Hursley
> IBM United Kingdom Ltd
> Phone internal: 245913, external: 01962 815913
> internet email: andrew_m_leonard at uk.ibm.com
>
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