RFR: 8370100: Redundant .png files in Linux app-image cause unnecessary bloat [v2]

[Alexey Semenyuk]

On Sat, 25 Oct 2025 04:23:23 GMT, Alexander Matveev <almatvee at openjdk.org> wrote:

>> Alexey Semenyuk has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains eight new commits since the last revision:
>> 
>>  - DefaultLauncherIcon: blessed-modifier-order.sh  fix
>>  - FileAssociations: revert redundant change
>>  - Fix fa icon verification on Linux
>>  - LinuxPackagingPipeline, WinPackagingPipeline: remove unused normalizeShortcuts() methods
>>  - IconTest: revamp
>>  - LinuxHelper: revamp
>>  - Don't add the default launcher icon to app image on Linux
>>  - Make Launcher interface provide complete information about the source of the launcher icon; Before this change, the function getting a resource for an additional launcher icon took both the additional launcher and the main launcher as input. Now its result doesn't depend on the main launcher.
>
> src/jdk.jpackage/share/classes/jdk/jpackage/internal/ApplicationBuilder.java line 175:
> 
>> 173:     }
>> 174: 
>> 175:     static <T extends Launcher> ApplicationLaunchers normalizeIcons(
> 
> Can you explain why we need this code?

Previously, [ApplicationImageUtils.createLauncherIconResource()](https://github.com/openjdk/jdk/blob/32697bf652429fa7247047465e365835dfa24b39/src/jdk.jpackage/share/classes/jdk/jpackage/internal/ApplicationImageUtils.java#L53) function required the `Application` instance to get the icon of a launcher because for additional launchers getting icon was a function taking the main launcher into account.

`normalizeIcons()` modifies application launchers so that they contain complete information about their icons.
The follow-up for this change, `ApplicationImageUtils.createLauncherIconResource()`, is modified to no longer require an `Application` instance.

There are other properties in additional launchers that depend on the main launcher: description, shortcuts. Each is calculated in a unique way. 

Descripton: https://github.com/openjdk/jdk/blob/32697bf652429fa7247047465e365835dfa24b39/src/jdk.jpackage/share/classes/jdk/jpackage/internal/FromParams.java#L232

Shortcuts:
https://github.com/openjdk/jdk/blob/32697bf652429fa7247047465e365835dfa24b39/src/jdk.jpackage/share/classes/jdk/jpackage/internal/FromParams.java#L176

So we have three functions doing the same thing: they calculate the value of a property of an additionl launcher from the value in the property file of the additional launcher and the value of this property of the main launcher. The logic is the same in all these functions: if an additional launcher doesn't explicitly set the value of a property, it should be copied from the main launcher.

I moved this logic to a single function - `ApplicationBuilder.normalizeLauncherProperty()`. Currently, it is used for launcher icons only, but later will be used for other launcher poroperties.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/27928#discussion_r2462907768