Not able to add classes in a directory to shared archive when using AppCDS

[David Holmes]

Moving to hotspot-runtime-dev

David

On 5/04/2018 7:15 PM, ashutosh mehra wrote:
> I am trying to use App CDS for a sample application.
> My class files are in a directory which I specify as the classpath.
> I want these classes to be included in shared archive.
> Directory structure is like this:
> $ tree
> .
> ├── classes
> │   ├── SampleClass.class
> │   └── SampleClass.java
> ├── TestCDS.class
> └── TestCDS.java
> 
> I performed following steps:
> 
> 1. Create the class list:
> $ java -Xshare:off -XX:+UseAppCDS -XX:DumpLoadedClassList=classes.list -cp
> .:classes TestCDS
> 
> This generated the list of classes including my application classes TestCDS
> and SampleClass.
> 
> 2. Create the shared archive:
> $ java -Xshare:dump -XX:+UseAppCDS -XX:SharedClassListFile=classes.list
> -XX:SharedArchiveFile=mycds.jcs -cp .:classes
> 
> I get following error message:
> 
> *narrow_klass_base = 0x0000000800000000, narrow_klass_shift = 3*
> *Allocated temporary class space: 1073741824 bytes at 0x00000008c0000000*
> *Allocated shared space: 3221225472 bytes at 0x0000000800000000*
> *Error: non-empty directory '.'*
> *Hint: enable -Xlog:class+path=info to diagnose the failure*
> *Error occurred during initialization of VM*
> *CDS allows only empty directories in archived classpaths*
> 
> Java version is:
> openjdk version "10" 2018-03-20
> OpenJDK Runtime Environment 18.3 (build 10+46)
> OpenJDK 64-Bit Server VM 18.3 (build 10+46, mixed mode)
> 
> I have also tried with Java 11 EA build but got same output.
> 
> Is this expected behavior? I am sure it would be useful for many if the
> classes loaded from a directory can also be stored in the shared archive.
> 
> Regards,
> Ashutosh
>