if (m.getVersioning() == null) {
                        m.setVersioning(new Versioning());
                    }

                    if (m.getVersioning().getSnapshot() == null) {
                        m.getVersioning().setSnapshot(new Snapshot());
                    }
                } else {
                    if ((m.getVersioning() != null)

                changed = true;
            }
        }

        Versioning versioning = sourceMetadata.getVersioning();
        if ( versioning != null )
        {
            Versioning v = getVersioning();
            if ( v == null )
            {
                v = new Versioning();
                setVersioning( v );
                changed = true;
            }

            Metadata repoMetadata, List<String> availableVersions) {
        Collection<String> versions = new LinkedHashSet<>();

        if ((repoMetadata != null) && (repoMetadata.getVersioning() != null)) {
            versions.addAll(repoMetadata.getVersioning().getVersions());
        }

        versions.addAll(availableVersions);

        List<ArtifactVersion> artifactVersions = new ArrayList<>(versions.size());