On Wed, 20 Nov 2024 14:26:27 GMT, Severin Gehwolf <sgehw...@openjdk.org> wrote:
> Please review this simple patch which adds a new external system property > `jdk.patched` when the runtime has been patched with the `--patch-module` > switch. This is useful for two reasons: 1) it allows one to determine at > run-time whether or not `--patch-module` has been used (by querying the said > property) 2) allows tools, such as `jlink` doing the same without needing to > expose internal properties the JVM sets on initialization. > > Testing: > > - [x] GHA (includes new test) > - [x] New jtreg test > > Thoughts? > Having now looked at #22037 which is what motivated this change, I now have a > more basic question. > > The `--patch-module` option is an option for the `java` command. The code > changes in this current PR is proposing to set a system property if `java` > was launched with `--patch-module=...`. The other PR is about image creation > using `jlink` command. Looking at the other PR, it proposes to look for the > presence of this system property to do some decisions during image creation. > However, when that `jlink` command is invoked, it's a completely different > process/runtime, so how would `--patch-module` for `java` setting a system > property propagate to that image creation `jlink` process? > > I am feeling that I have misunderstood what's being proposed here. This is the corner case of jlink being run with -J--patch-module or "in-process" with ToolProvider. I see Severin recently added to the link of restrictions in JEP 493 but I'm not sure that it rises to the level that it should be mentioned in the JEP. ------------- PR Comment: https://git.openjdk.org/jdk/pull/22277#issuecomment-2490292591
