On Tue, 23 Sep 2025 19:11:41 GMT, David Beaumont <[email protected]> wrote:
> C++ changes for supporting preview mode when preview mode resources (with new
> location flags) are available.
>
> At the moment, this code will operate on non-preview jimage files (1.0) and
> act as if no preview resources are available by virtue of the default value
> for missing attributes being zero (which matches location flags for "normal"
> entries).
Disclaimer: I can only speak for the runtime portions of the code.
src/hotspot/share/classfile/classLoader.cpp line 251:
> 249: // Closes and clears the JImage file reference (this will only be called
> during shutdown).
> 250: static void jimage_close() {
> 251: if (JImage_file != nullptr) {
I'm not familiar with jimage at all, is there as reason we could close a
non-open jimage? And following from that, can we guarantee to not call
jimage_open on an open jimage? (Maybe an assert should guard it?)
src/hotspot/share/classfile/classLoader.cpp line 291:
> 289: // the preview mode to be manually specified, so must not be accessible
> outside this
> 290: // class. ClassPathImageEntry manages all calls for resources after
> startup is complete.
> 291: static JImageLocationRef jimage_find_resource(const char* module_name,
This function makes the rest of the code more legible. Thanks!
src/java.base/share/native/libjimage/imageFile.cpp line 326:
> 324: // for preview mode. Preview mode changes do not modify any
> structure,
> 325: // so a 1.0 file will look like a jimage without any preview
> resources.
> 326: // TODO: Restore equality check for MINOR_VERSION.
Is this something you still have to address in this PR?
-------------
Marked as reviewed by phubner (Author).
PR Review:
https://git.openjdk.org/valhalla/pull/1618#pullrequestreview-3322083982
PR Review Comment:
https://git.openjdk.org/valhalla/pull/1618#discussion_r2418991622
PR Review Comment:
https://git.openjdk.org/valhalla/pull/1618#discussion_r2418995309
PR Review Comment:
https://git.openjdk.org/valhalla/pull/1618#discussion_r2418997876
