On Sat, 22 Nov 2025 07:37:01 GMT, Steve Armstrong <[email protected]> wrote:
> The three AtomicXxxFieldUpdater classes (AtomicIntegerFieldUpdater,
> AtomicLongFieldUpdater, and AtomicReferenceFieldUpdater) contain duplicate
> field validation and access checking logic in their constructors and helper
> methods.
>
> This change extracts the common validation and utility methods into a new
> package-private class FieldUpdaterUtil to eliminate code duplication and
> improve maintainability.
>
> Changes:
> - Added new FieldUpdaterUtil class with static utility methods:
> * validateField() - validates field type, volatile, and static checks
> * computeAccessClass() - determines correct class for access checks
> * isSamePackage() - checks if two classes are in same package
> * isAncestor() - checks classloader delegation chain
>
> - Updated AtomicIntegerFieldUpdater to use FieldUpdaterUtil
> * Simplified constructor to use validateField() and computeAccessClass()
> * Removed duplicate isAncestor() and isSamePackage() methods
>
> - Updated AtomicLongFieldUpdater to use FieldUpdaterUtil
> * Simplified constructor to use validateField() and computeAccessClass()
> * Removed duplicate isAncestor() and isSamePackage() methods
>
> - Updated AtomicReferenceFieldUpdater to use FieldUpdaterUtil
> * Simplified constructor to use validateField() and computeAccessClass()
> * Removed duplicate isAncestor() and isSamePackage() methods
>
> Existing tests in test/jdk/java/util/concurrent/tck and
> test/jdk/java/util/concurrent/atomic verify that the refactoring preserves
> the original behavior.
This can also get rid of the last remaining uses of the legacy
`sun.reflect.misc.ReflectUtil`:
--------------------------------------------------------------------------------
(`jdk.internal.reflect.Reflection` is already imported for
`Reflection.getCallerClass()`)
src/java.base/share/classes/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java
line 395:
> 393: modifiers = field.getModifiers();
> 394: sun.reflect.misc.ReflectUtil.ensureMemberAccess(
> 395: caller, tclass, null, modifiers);
Suggestion:
Reflection.ensureMemberAccess(
caller, tclass, null, modifiers);
src/java.base/share/classes/java/util/concurrent/atomic/AtomicLongFieldUpdater.java
line 390:
> 388: modifiers = field.getModifiers();
> 389: sun.reflect.misc.ReflectUtil.ensureMemberAccess(
> 390: caller, tclass, null, modifiers);
Suggestion:
Reflection.ensureMemberAccess(
caller, tclass, null, modifiers);
src/java.base/share/classes/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.java
line 352:
> 350: modifiers = field.getModifiers();
> 351: sun.reflect.misc.ReflectUtil.ensureMemberAccess(
> 352: caller, tclass, null, modifiers);
Suggestion:
Reflection.ensureMemberAccess(
caller, tclass, null, modifiers);
-------------
PR Review: https://git.openjdk.org/jdk/pull/28464#pullrequestreview-3498156901
PR Review Comment: https://git.openjdk.org/jdk/pull/28464#discussion_r2554468849
PR Review Comment: https://git.openjdk.org/jdk/pull/28464#discussion_r2554469008
PR Review Comment: https://git.openjdk.org/jdk/pull/28464#discussion_r2554469107
