[INFO] --- maven-bundle-plugin:3.2.0:manifest (generate-manifest) @ undertow-core ---
[ERROR] Manifest io.undertow:undertow-core:jar:2.0.21.Final-SNAPSHOT : Classes found in the wrong directory: {META-INF/versions/9/io/undertow/util/FastConcurrentDirectDeque$CLDSpliterator.class=io.undertow.util.FastConcurrentDirectDeque$CLDSpliterator, META-INF/versions/9/io/undertow/util/FastConcurrentDirectDeque$Itr.class=io.undertow.util.FastConcurrentDirectDeque$Itr, META-INF/versions/9/io/undertow/util/FastConcurrentDirectDeque$AbstractItr.class=io.undertow.util.FastConcurrentDirectDeque$AbstractItr, META-INF/versions/9/io/undertow/util/FastConcurrentDirectDeque$Node.class=io.undertow.util.FastConcurrentDirectDeque$Node, META-INF/versions/9/io/undertow/util/FastConcurrentDirectDeque$DescendingItr.class=io.undertow.util.FastConcurrentDirectDeque$DescendingItr, META-INF/versions/9/io/undertow/util/FastConcurrentDirectDeque.class=io.undertow.util.FastConcurrentDirectDeque}
[ERROR] Error(s) found in manifest configuration
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] Undertow 2.0.21.Final-SNAPSHOT ..................... SUCCESS [  2.294 s]
[INFO] Undertow Parser Generator .......................... SUCCESS [  5.834 s]
[INFO] Undertow Core ...................................... FAILURE [ 27.628 s]
[INFO] Undertow Servlet ................................... SKIPPED
[INFO] Undertow WebSockets JSR356 implementations ......... SKIPPED
[INFO] Undertow Examples .................................. SKIPPED
[INFO] Undertow Karaf Features ............................ SKIPPED
[INFO] Undertow Benchmarks 2.0.21.Final-SNAPSHOT .......... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 36.227 s
[INFO] Finished at: 2019-05-29T12:24:27+02:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.felix:maven-bundle-plugin:3.2.0:manifest (generate-manifest) on project undertow-core: Error(s) found in manifest configuration -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
[ERROR] 
[ERROR] After correcting the problems, you can resume the build with the command
[ERROR]   mvn <goals> -rf :undertow-core