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
