Accessing module internals from bytecode rewriting agent

[Jeremy Manson]

Thanks, Alan.  I don't use byteman, and my agent wasn't working out of the
box to redefine JDK classes...  I guess I can keep digging.

Jeremy

On Mon, Apr 24, 2017 at 11:35 PM, Alan Bateman <Alan.Bateman at oracle.com>
wrote:

> On 25/04/2017 07:22, Jeremy Manson wrote:
>
> :
>>
>> The instrument API specifically supports a Boot-Class-Path attribute in
>> the
>> MANIFEST, as well as Instrumentation.appendToBootStrapClassLoaderSearch.
>> I
>> had been using that as a way to make it possible to rewrite JDK internals
>> (add allocation instrumentation to them).
>>
> I wouldn't expect any issues with that scenario as the VM adds the
> readability needed for this to work. From the javadoc:
>
> "As an aid to agents that deploy supporting classes on the search path of
> the bootstrap class loader, or the search path of the class loader that
> loads the main agent class, the Java virtual machine arranges for the
> module of transformed classes to read the unnamed module of both class
> loaders."
>
> Instead, I think the issue in Martin's mail is more to do with Byteman
> moving to java.lang.invoke and running into an issue getting full power
> lookups to fully privileged classes.
>
> -Alan.
>