Bug ID: JDK-8230501 Class data support for hidden classes

JDK-8230501 : Class data support for hidden classes

Type: Enhancement
Component: core-libs
Sub-Component: java.lang.invoke

Priority: P3
Status: Resolved
Resolution: Fixed

Submitted: 2019-09-03
Updated: 2020-12-07
Resolved: 2020-12-01

Versions (Unresolved/Resolved/Fixed)

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Resolved: Release in which this issue/RFE has been resolved.
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JDK 16
16 b27Fixed

Related Reports

Blocks :	JDK-8243492 - SIGSEGV when getting class data via condy from a virtual method
CSR :	JDK-8256214 - Class data support for hidden classes
Relates :	JDK-8238693 - Two JCK api/java_lang/invoke/MethodHandles/Lookup tests fail in valhalla nestmates repo
Relates :	JDK-8243287 - Removal of Unsafe::defineAnonymousClass
Relates :	JDK-8209679 - JVM support for "classData"
Relates :	JDK-8242451 - ensure semantics of non-capturing lambdas are preserved independent of execution mode
Relates :	JDK-8171335 - MethodHandle.Lookup functionality to define a nestmate class

Sub Tasks

JDK-8238693 :

Two JCK api/java_lang/invoke/MethodHandles/Lookup tests fail in valhalla nestmates repo - Resolved

Description

One feature of `Unsafe::defineAnonymousClass`  is constant pool patching that is used by LambdaForm and few external libraries [1].

One idea is to allow a dynamically generated class be defined with a class data which can only be obtained by a full-power lookup (e.g. `Lookup::classData` method).

[1] http://jigsaw-dev.1059479.n5.nabble.com/Remove-sun-misc-Unsafe-defineAnonymousClass-td5715601.html

Comments

Changeset: 4356469a Author: Mandy Chung <mchung@openjdk.org> Date: 2020-12-01 00:24:40 +0000 URL: https://git.openjdk.java.net/jdk/commit/4356469a

01-12-2020

See John's comment on class data: https://bugs.openjdk.java.net/browse/JDK-8171335?focusedCommentId=14300071&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14300071 and also from JDK-8209679.

21-04-2020