On Thu, 17 Feb 2022 01:38:42 GMT, Joe Darcy <da...@openjdk.org> wrote:
>> This is an early review of changes to better model JVM access flags, that is >> "modifiers" like public, protected, etc. but explicitly at a VM level. >> >> Language level modifiers and JVM level access flags are closely related, but >> distinct. There are concepts that overlap in the two domains (public, >> private, etc.), others that only have a language-level modifier (sealed), >> and still others that only have an access flag (synthetic). >> >> The existing java.lang.reflect.Modifier class is inadequate to model these >> subtleties. For example, the bit positions used by access flags on different >> kinds of elements overlap (such as "volatile" for fields and "bridge" for >> methods. Just having a raw integer does not provide sufficient context to >> decode the corresponding language-level string. Methods like >> Modifier.methodModifiers() were introduced to cope with this situation. >> >> With additional modifiers and flags on the horizon with projects like >> Valhalla, addressing the existent modeling deficiency now ahead of time is >> reasonable before further strain is introduced. >> >> This PR in its current form is meant to give the overall shape of the API. >> It is missing implementations to map from, say, method modifiers to access >> flags, taking into account overlaps in bit positions. >> >> The CSR https://bugs.openjdk.java.net/browse/JDK-8281660 will be filled in >> once the API is further along. > > Joe Darcy has updated the pull request with a new target base due to a merge > or a rebase. The incremental webrev excludes the unrelated changes brought in > by the merge/rebase. The pull request contains ten additional commits since > the last revision: > > - Update JVMS references. > - Merge branch 'master' into JDK-8266670 > - Reorder constants by mask value per review feedback. > - Merge branch 'master' into JDK-8266670 > - Respond to more review feedback. > - Respond to review feedback explicitly stating returned sets are immutable. > - Fix typo from review feedback. > - Merge branch 'master' into JDK-8266670 > - JDK-8266670: Better modeling of modifiers in core reflection The jvms also has `access_flags` for parameters. [4.7.24. The MethodParameters Attribute](https://docs.oracle.com/javase/specs/jvms/se17/html/jvms-4.html#jvms-4.7.24) Even if java.lang.reflect.Parameter is not a "Member", it would be useful for Parameter to have an `accessFlags()` method and loosen up the spec for AccessFlag to allow its use in Parameter. Its access flags have the same underlying bit patterns and definitions. ------------- PR: https://git.openjdk.java.net/jdk/pull/7445
