[jira] [Commented] (MNG-6506) Mojos are unable to load package annotations on Java >= 9

["Andreas Veithen (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/MNG-6506?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16674425#comment-16674425 ] 

Andreas Veithen commented on MNG-6506:
--------------------------------------

A minimal test case can be found here: [https://github.com/veithen/MNG-6506]. The project builds successfully on Java 8 and fails on Java 9. 

> Mojos are unable to load package annotations on Java >= 9
> ---------------------------------------------------------
>
>                 Key: MNG-6506
>                 URL: https://issues.apache.org/jira/browse/MNG-6506
>             Project: Maven
>          Issue Type: Bug
>          Components: Class Loading
>    Affects Versions: 3.6.0
>            Reporter: Andreas Veithen
>            Priority: Major
>
> On Java 9 and above, calls to {{java.lang.Package.getAnnotation(Class)}} from within a Mojo always return {{null}} (unless the {{package-info}} class has been loaded by some other means before).
> The reason appears to be an incompatibility between Java 9 and Plexus Classworlds:
> * Java 9 ultimately calls {{findClass}} (instead of {{loadClass}}) to get the {{package-info}} class.
> * The {{findClass}} implementation in {{ClassRealm}} always throws {{ClassNotFoundException}}: https://github.com/sonatype/plexus-classworlds/blob/plexus-classworlds-2.5.2/src/main/java/org/codehaus/plexus/classworlds/realm/ClassRealm.java#L275.
> This in particular affects plugins that interact with the JAXB API because it relies on package annotations. A workaround is to preload the required {{package-info}} classes using {{loadClass}}; see e.g. http://svn.apache.org/viewvc?rev=1845026&view=rev.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)