Accessing Attach API?

[Aleksey Shipilev]

On 04/13/2016 12:08 PM, Aleksey Shipilev wrote:
> OpenJDK JOL is using Attach API to get the access to Instrumentation
> instance without forcing user to -javaagent: the JAR. I think ByteBuddy
> is using similar mechanism.
> 
> How is one supposed to use Attach API these post-Jigsaw days?
> 
> Before JDK 9, we could poll VirtualMachine from tools.jar, and then use
> the snippet from the original Javadoc:
>  http://docs.oracle.com/javase/8/docs/jdk/api/attach/spec/com/sun/tools/attach/VirtualMachine.html
> 
> ...then, after tools.jar was gone in JDK 9, the classes were still
> available on classpath, and we could do, e.g.:
> System.getClassloader().loadClass("com.sun.tools.attach.VirtualMachine").
> 
> Now, with Jigsaw integrated, this class is not available, because
> jdk.attach is not a platform module. I see there are attempts to expose
> SPI via com.sun.tools.attach.spi.AttachProvider -- but of course,
> AttachProvider is also not available to feed it to ServiceLoader.

Wait, I confused myself with multiple JDK builds here. This actually
works in JDK 9b113:

Class<?> vmClass = ClassLoader.getSystemClassLoader()
                      .loadClass("com.sun.tools.attach.VirtualMachine");

Therefore, we are fine at the moment. Is this behavior to stay?

Thanks,
-Aleksey