RFR: 8257845: Integrate JEP 390

[Mandy Chung]

On Sat, 5 Dec 2020 01:46:31 GMT, Dan Smith <dlsmith at openjdk.org> wrote:

> Integration of [JEP 390](https://bugs.openjdk.java.net/browse/JDK-8249100).
> 
> Development has been broken into 5 tasks, each with its own JBS issue:
> - Deprecate wrapper class constructors for removal (rriggs)
> - Revise "value-based class" & apply to wrappers (dlsmith)
> - Define & apply annotation jdk.internal.ValueBased (rriggs)
> - Add 'lint' warning for @ValueBased classes (sadayapalam)
> - Diagnose synchronization on @ValueBased classes (lfoltan)
> 
> All changes have been previously reviewed and integrated into the [`jep390` branch](https://github.com/openjdk/valhalla/tree/jep390) of the `valhalla` repository. See the subtasks of the 5 JBS issues for these changes, including discussion and links to reviews. (Reviewers: mchung, dlsmith, jlaskey, rriggs, lfoltan, fparain, hseigel.)
> 
> CSRs have also been completed or are nearly complete:
> 
> - [JDK-8254324](https://bugs.openjdk.java.net/browse/JDK-8254324) for wrapper class constructor deprecation
> - [JDK-8254944](https://bugs.openjdk.java.net/browse/JDK-8254944) for revisions to "value-based class"
> - [JDK-8256023](https://bugs.openjdk.java.net/browse/JDK-8256023) for new `javac` lint warnings
> 
> Here's an overview of the files changed:
> 
> - `src/hotspot`: implementing diagnostics when `monitorenter` is applied to an instance of a class tagged with `jdk.internal.ValueBased`. This enhances previous work that produced such diagnostics for the primitive wrapper classes.
> 
> - `src/java.base/share/classes/java/lang`: deprecating for removal the wrapper class constructors; revising the definition of "value-based class" in `ValueBased.html` and the description used by linking classes; applying "value-based class" to the primitive wrapper classes; marking value-based classes with `@jdk.internal.ValueBased`.
> 
> - `src/java.base/share/classes/java/lang/constant`: no longer designating these classes as "value-based", since they rely heavily on field inheritance.
> 
> - `src/java.base/share/classes/java/time`: revising the description used to link to `ValueBased.html`; marking value-based classes with `@jdk.internal.ValueBased`.
> 
> - `src/java.base/share/classes/java/util`: revising the description used to link to `ValueBased.html`; marking value-based classes with `@jdk.internal.ValueBased`.
> 
> - `src/java.base/share/classes/jdk/internal`: define the `@jdk.internal.ValueBased` annotation.
> 
> - `src/java.management.rmi`: removing uses of wrapper class constructors.
> 
> - `src/java.xml`: removing uses of wrapper class constructors.
> 
> - `src/jdk.compiler`: implementing the `synchronization` lint category, which reports attempts to synchronize on classes and interfaces annotated with `@jdk.internal.ValueBased`.
> 
> - `src/jdk.incubator.foreign`: revising the description used to link to `ValueBased.html`. (Applying `@jdk.internal.ValueBased` would require a special module export, which was not deemed necessary for an incubating API.)
> 
> - `src/jdk.internal.vm.compiler`: suppressing `javac` deprecation and synchronization warnings in tests
> 
> - `src/jdk.jfr`: supplementary changes for HotSpot diagnostics
> 
> - `test`: testing new `javac` and HotSpot behavior; removing usages of deprecated wrapper class constructors from tests, or suppressing deprecation warnings; revising the description used to link to `ValueBased.html`.

core-libs and hotspot change look okay.

-------------

Marked as reviewed by mchung (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/1636