Avoiding sun.misc.Unsafe and embracing modules in Java libraries: missing links

Rafael Winterhalter rafael.wth at gmail.com
Fri Apr 13 19:49:54 UTC 2018

Yes, of course. This was merely a proof of concept to show that it works.

2018-04-13 8:48 GMT+02:00 Peter Levart <peter.levart at gmail.com>:

> On 04/12/18 10:40, Alan Bateman wrote:
> On 11/04/2018 21:07, Rafael Winterhalter wrote:
> I do not think that this is possible. If the module containing the
> interface does not open a package, I cannot change the privileges of the
> main module such that I can resolve a method handle for invoking the
> special invocation.
> I just tried this out too and I did not find a way, could you suggest how
> to change my code for being able to do so?
> If the interface is public in an exported package (no need for the package
> to be open) then the proxy will be generated into the unnamed module. So
> easy to get a Lookup to the proxy class and you can use this as the special
> caller. Can you change your invocation handler to the following and try it:
> Class<?> proxyClass = proxy.getClass();
> Main.class.getModule().addReads(proxyClass.getModule());
> Lookup lookup = MethodHandles.privateLookupIn(proxyClass,
> MethodHandles.lookup());
> MethodType mt = MethodType.methodType(String.class);
> return lookup.findSpecial(iface, "foo", mt, proxyClass).bindTo(proxy).invokeWithArguments();
> -Alan
> This works logically, but performance wise I would 1st create a proxy
> class, lookup the direct method handles I want to invoke, transform them to
> take Object 'proxy' instance as 1st argument and the rest of arguments as
> an Object[] and return an Object. I would cache the resulting MHs in the
> specific (constant if possible) InvocationHandler. Each invocation would
> then only select the right cached MH as quickly as possible and do return
> mh.invokeExact(proxy, args);
> Peter

More information about the jigsaw-dev mailing list