*
     * @param artifactType the type of artifacts to retrieve
     * @return an array of installed artifacts
     */
    public Artifact[] getInstalledArtifacts(final ArtifactType artifactType) {
        if (artifactType == ArtifactType.UNKNOWN) {
            final File[] jarFiles = ResourceUtil.getPluginJarFiles((d, n) -> {
                for (final ArtifactType type : ArtifactType.values()) {

import org.codelibs.core.stream.StreamUtil;
import org.codelibs.fess.exception.ThemeException;
import org.codelibs.fess.helper.PluginHelper.Artifact;
import org.codelibs.fess.helper.PluginHelper.ArtifactType;
import org.codelibs.fess.util.ResourceUtil;

/**
 * Helper class for managing theme installation and uninstallation.
 * Handles the extraction and deployment of theme files from JAR artifacts.
 */

     */
    protected List<String> loadDataStoreNameList() {
        final Set<String> nameSet = new HashSet<>();
        final File[] jarFiles = ResourceUtil.getPluginJarFiles(PluginHelper.ArtifactType.DATA_STORE.getId());
        if (jarFiles == null) {
            return nameSet.stream().sorted().collect(Collectors.toList());
        }
        for (final File jarFile : jarFiles) {