RFR: 8155591: Misleading warning when not overriding close method in interface extending AutoCloseable [v4]

[Jan Lahoda]

On Thu, 6 Nov 2025 02:53:47 GMT, Archie Cobbs <acobbs at openjdk.org> wrote:

>> The compiler generates a warning if you declare a `close()` method that throws any supertype of `InterruptedException` in a class or interface extending `AutoCloseable`. This is because suppressed `InterruptedException`'s are likely to lead to misbehavior at runtime.
>> 
>> However, this feature also generates a warning due to `AutoCloseable.close()` itself, if you simply inherit it. For example:
>> 
>> $ cat MyClass.java
>> public interface MyClass extends AutoCloseable {
>> }
>> $ javac -Xlint:try MyClass.java
>> MyClass.java:1: warning: [try] auto-closeable resource MyClass has a member method close() that could throw InterruptedException
>> public interface MyClass extends AutoCloseable {
>>        ^
>> 1 warning
>> 
>> The warning is not useful because `AutoCloseable.close()` is abstract and so it's going to be some other class' job to deal with the throws clause.
>> 
>> This change prevents `AutoCloseable.close()` itself from triggering the warning in a class declaration. We preserve the existing behavior in which a warning is generated at the use site (i.e., at the try-with-resources statement).
>
> Archie Cobbs has updated the pull request incrementally with three additional commits since the last revision:
> 
>  - Add another regression test case.
>  - Unbreak existing regression test after previous commit.
>  - Show warnings for declared close() at declaration site.

Looks good to me.

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Marked as reviewed by jlahoda (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27062#pullrequestreview-3427566595