----- Original Message ----- > From: "Chen Liang" <li...@openjdk.org> > To: "core-libs-dev" <core-libs-dev@openjdk.org>, "hotspot-dev" > <hotspot-...@openjdk.org>, kulla-...@openjdk.org > Sent: Thursday, May 23, 2024 1:28:01 PM > Subject: Re: RFR: 8242888: Convert dynamic proxy to hidden classes
> On Thu, 23 May 2024 03:28:30 GMT, Chen Liang <li...@openjdk.org> wrote: > >> Please review this change that convert dynamic proxies implementations to >> hidden >> classes, intended to target JDK 24. >> >> Summary: >> 1. Adds new implementation while preserving the old implementation behind >> `-Djdk.reflect.useLegacyProxyImpl=true` in case there are compatibility >> issues. >> 2. ClassLoader.defineClass0 takes a ClassLoader instance but discards it in >> native code; I updated native code to reuse that ClassLoader for Proxy >> support. >> 3. ProxyGenerator changes mainly involve using Class data to pass Method list >> (accessed in a single condy) and removal of obsolete setup code generation. >> >> Testing: tier1 and tier2 have no related failures. >> >> Comment: Since #8278, Proxy has been converted to ClassFile API, and >> infrastructure has changed; now, the migration to hidden classes is much >> cleaner and has less impact, such as preserving ProtectionDomain and dynamic >> module without "anchor classes", and avoiding java.lang.invoke package. > > A CSR targeting 24 describing the compatibility concerns and behavioral > differences is here, somehow not linked by skara: > https://bugs.openjdk.org/browse/JDK-8332770 > The incompatibilities were much greater in the previous iterations of this > issue, such as in dynamic modules, serialization, and in proxy class > protection > domain. Now these aspects are addressed by this patch, the only real one left > is the change in stack trace. Feel free to raise other incompatibilities you > have discovered. I wonder if instead of using hidden classes, we should not use usual named classes and add a new Lookup.defineClass() that takes a classData as parameter. This will solve the both the problem of the stacktrace and the problem of the roundtrip proxyClass != Class.forName(proxyClass.getName()). Rémi > > ------------- > > PR Comment: https://git.openjdk.org/jdk/pull/19356#issuecomment-2126869679
