RFR: 8357714: AudioClip.play crash on macOS when loading resource from jar

[Alexander Matveev]

On Tue, 8 Jul 2025 01:03:23 GMT, Alexander Matveev <almatvee at openjdk.org> wrote:

>> In case of jar, the ConnectionHolder is a `MemoryConnectionHolder` (because Locator already has a cacheEntry) which has true for isRandomAccess. 
>> The cacheEntry is created by the `NativeMediaAudioClip<init>` which is indirectly called by the AudioClip constructor.
>> 
>> In case `readNextBlock` is used on a MemoryConnectionHolder, it seems all chuncks are asked  and played simultaneously (bug in MemoryConnectionHolder.readNextBlock?). With `readBlock` the order and sequence seem to be ok.
>> 
>> Alternatively, we might try to use the already-created ConnectionHolder instead of creating a new one in OSXMediaPlayer.mm.
>
> Yes, you right `MemoryConnectionHolder` in case of jar, but only for AudioClip. MediaPlayer does not use it. I tested AudioClip with jar with and without random access. Without random access I only hear some clicking sounds, so looks like it does not work completely. With random access I can only hear audio for like 30 seconds and then it loops, so looks like it is broken as well.
> 
> Can you play audio file correctly via AudioClip?

I figure it out. Seek is ignored for random access, so setting `pos = 0` will always read from begging of the file. We should read from `dataRequest.requestedOffset`. I am attaching proposed patch which I tested and works fine.

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

PR Review Comment: https://git.openjdk.org/jfx/pull/1839#discussion_r2191370087