code: @Override
      public void artifactDescriptorInvalid(RepositoryEvent event) {
          log.warning("Invalid artifact descriptor for " + event.getArtifact() + ": " + event.getException().getMessage());
      }
docs: /*
  (non-Javadoc)
  
  @see org.eclipse.aether.util.listener.AbstractRepositoryListener#
  artifactDescriptorInvalid(org.eclipse.aether.RepositoryEvent)