@NotNull
  public List<MavenArtifact> findArtifacts(@Nullable MavenId mavenId) {
    if (mavenId == null) return Collections.emptyList();

    return findArtifacts(mavenId.getGroupId(), mavenId.getArtifactId(), mavenId.getVersion());
  }
@NotNull
  public List<MavenArtifact> findArtifacts(@Nullable MavenId mavenId)