RFR: 8378111: Migrate java/util/jar tests to JUnit [v2]

[Justin Lu]

On Thu, 19 Feb 2026 21:12:41 GMT, Eirik Bjørsnøs <eirbjo at openjdk.org> wrote:

>> Justin Lu has updated the pull request incrementally with three additional commits since the last revision:
>> 
>>  - Eirik comments
>>  - Naoto comment
>>  - Andrey comments
>
> test/jdk/java/util/jar/Manifest/IncludeInExceptionsTest.java line 47:
> 
>> 45:  * @run junit/othervm -Djdk.includeInExceptions=jar IncludeInExceptionsTest
>> 46:  * @run junit/othervm IncludeInExceptionsTest
>> 47:  * @summary Verify that the property jdk.net.includeInExceptions works as expected
> 
> `jdk.net.includeInExceptions` is not the property being tested here, should be `jdk.includeInExceptions` ?

Thanks for the review and helpful comments!

Looks like this property was renamed in [JDK-8207846](https://bugs.openjdk.org/browse/JDK-8207846).

> test/jdk/java/util/jar/TestExtra.java line 78:
> 
>> 76:     @Test
>> 77:     void extraHeaderPlusDataTest() throws IOException {
>> 78:         new TestExtra().testHeaderPlusData();
> 
> Consider letting JUnit handle the instance state management  to avoid these wrapper test methods.

The reason I wrapped those tests was to control the executing test class, (i.e. `TestExtra` vs `TestJarExtra`). However, you are right that it's clutter and also doubling the instances. Keeping the inner `TestJarExtra` class is problematic because in its current `static` form, tests have to be run by the outer class leading to the manual ctors. If we make it a non static inner class and use `@nested` it causes a JUnit cycle error for the class hierarchy since the inner class also extends the outer class.

I pulled `TestJarExtra` into its own test file which gets rid of the manual instance handling and is cleaner.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/29828#discussion_r2834609443
PR Review Comment: https://git.openjdk.org/jdk/pull/29828#discussion_r2834609236