JPackage with a modular application fails to load record class files even with --enable-preview

[Johannes Kuhn]

Relevant StackOverlow question: 
https://stackoverflow.com/questions/61504956/records-in-jlinked-application-throws-exception

It talks about JLink, but the error message is the same, so I expect the 
same root cause:
The ASM version shipped with JDK 14 doesn't support records yet. It is 
already fixed for JDK 15.

- Johannes

On 09-Jun-20 16:40, Andy Herrick wrote:
> So when you use the jpackage option "--java-options --enable-preview" 
> it appears to work with a non-modular jar, but not with a modular jar ?
>
> I think I can create a testcase for that.
>
> Have you tried it with the jpackage from a preview release of JDK15  
> (https://jdk.java.net/15/) ?
>
> Can you look at the runtime in the app-image of the failing case, and 
> see if the preview module is there ?  Perhaps the problem is the way 
> jpackage invokes jlink.
>
> A final thing you can try is run jlink yourself, and use the resulting 
> runtime-image in jpackage args.
>
> /Andy
>
> On 6/7/2020 9:07 AM, Markus Jevring wrote:
>> I have this app, which uses Java 14 with –enable-preview and records. 
>> If I turn it in to a normal non-modular jar, it works with both java 
>> -jar –enable-preview myapp.jar, and with a native image built with 
>> jpackage. However, when i turn it into a modular jar, I can still 
>> launch it with java –enable-preview –module-path ... –module ..., 
>> but  when I try to create a native image using jpackage usign the 
>> same modular flags, launching it fails. I get a dialog box saying 
>> “Failed to launch JVM”, and if I enable –win-console when I build it 
>> and relaunch it, it tells me this:
>>
>> Exception in thread "main" java.lang.ClassFormatError: Invalid 
>> constant pool index 31 for name in Record attribute in class file 
>> net/jevring/frequencies/v2/input/KeyTimings$Note
>>          at java.base/java.lang.ClassLoader.defineClass2(Native Method)
>>          at java.base/java.lang.ClassLoader.defineClass(Unknown Source)
>>          at 
>> java.base/java.security.SecureClassLoader.defineClass(Unknown Source)
>>          at 
>> java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(Unknown 
>> Source)
>>          at 
>> java.base/jdk.internal.loader.BuiltinClassLoader.findClassInModuleOrNull(Unknown 
>> Source)
>>          at 
>> java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(Unknown 
>> Source)
>>          at 
>> java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown 
>> Source)
>>          at 
>> java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(Unknown 
>> Source)
>>          at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
>>          at 
>> frequencies/net.jevring.frequencies.v2.input.KeyTimings.<init>(Unknown 
>> Source)
>>          at 
>> frequencies/net.jevring.frequencies.v2.Thief.<init>(Unknown Source)
>>          at frequencies/net.jevring.frequencies.v2.Main.main(Unknown 
>> Source)
>>
>> Note, above, is a record. I tried moving it out to a separate class, 
>> and I still got the same error. When I converted Note to a normal 
>> class, it started complaining about the next record it cound.
>> I know that it’s picking up the –enable-preview java option, because 
>> when I omit that, it complains about the class file version being wrong.
>>
>> Since I can run it just fine using “java -jar”, and it works fine 
>> under all other circumstances, I must conclude that there’s something 
>> wrong with the intersection of modular jars and jpackage.
>> I’ve googled around plenty, and I haven’t found anything that might 
>> help me. I’m not sure if this is a call for help or a bug report, 
>> though I’d like to consider it the latter =)
>>
>> I put what I had on a branch: 
>> https://bitbucket.org/jevring/frequencies/branch/java-modules
>> I realize it’s not a small self-contained example that replicates the 
>> issue, and for that I’m sorry. If someone is interested about this, I 
>> could try to make one.