RFR: 8350601: Miscellaneous updates to jpackage test lib [v4]

[Alexander Matveev]

On Tue, 25 Feb 2025 15:48:29 GMT, Alexey Semenyuk <asemenyuk at openjdk.org> wrote:

>> - Unify TKit.createTempDirectory() and TKit.createTempFile() functions. Remove `throws IOexception` from their signatures. Add relevant tests.
>>  - JPackageCommand.java: remove try/catch(IOexception) around `TKit.createTempDirectory()` call.
>>  - AppImagePackageTest.java: replace `TKit.createTempDirectory(null)` with `TKit.createTempDirectory("appimage")` to fix NPE.
>>  - Make `TKit.assertDirectoryExists(Path, Optional<Boolean>)` private. This is internal and shouldn't be exposed.
>>  - add `TKit.assertEquals(boolean, boolean)` and `TKit.assertNotEquals(boolean, boolean)` with tests.
>>  - AdditionalLauncher.java: remove redundant code duplicating functionality of `TKit.createTempFile()` (should have been cleaned long ago).
>>  - JPackageCommand.java: add a check for the main jar in the app image if the main jar was specified. Missing part of [JDK-8325089](https://bugs.openjdk.org/browse/JDK-8325089).
>
> Alexey Semenyuk has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Better exception message

Looks good.

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

Marked as reviewed by almatvee (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/23754#pullrequestreview-2642475227