@Test
    public void test_loadDataStoreNameList_validXml() throws Exception {
        // Create test JAR with valid XML
        final File jarFile = new File(tempDir, "test-datastore.jar");
        createTestJarWithXml(jarFile,
                "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" + "<components>\n"
                        + "  <component class=\"org.codelibs.fess.ds.impl.CsvDataStore\"/>\n"

                    final JarURLConnection jarURLConnection = (JarURLConnection) resource.openConnection();
                    try (JarFile jarFile = jarURLConnection.getJarFile()) {
                        final Enumeration<JarEntry> entries = jarFile.entries();
                        while (entries.hasMoreElements()) {
                            final JarEntry entry = entries.nextElement();

                if (form.jarFile == null) {
                    throwValidationError(messages -> messages.addErrorsPluginFileIsNotFound(GLOBAL, form.id), this::asListHtml);
                }
                if (!form.jarFile.getFileName().endsWith(".jar")) {
                    throwValidationError(messages -> messages.addErrorsFileIsNotSupported(GLOBAL, form.jarFile.getFileName()),

    protected void appendJarFile(final String cpSeparator, final StringBuilder buf, final File libDir, final String basePath) {
        final File[] jarFiles = libDir.listFiles((FilenameFilter) (dir, name) -> name.toLowerCase().endsWith(".jar"));
        if (jarFiles != null) {
            for (final File file : jarFiles) {
                buf.append(cpSeparator);
                buf.append(basePath);
                buf.append(file.getName());

        File[] jarFiles = ResourceUtil.getJarFiles("fess");
        assertNotNull(jarFiles);
        // Should return empty array when no servlet context available in test
        assertEquals(0, jarFiles.length);

        // Test with empty prefix
        jarFiles = ResourceUtil.getJarFiles("");
        assertNotNull(jarFiles);
        assertEquals(0, jarFiles.length);
    }

    @Test

        // fess.var.path and fess.conf.path not set

        final File varFile = new File(varDir.toFile(), "test.txt");
        varFile.getParentFile().mkdirs();
        varFile.createNewFile();

        // Should throw because only fess.webapp.path is set and the file is not under it
        assertThrows(IllegalArgumentException.class, () -> action.validateFilePath(varFile.getAbsolutePath()));
    }

            final List<Artifact> list = new ArrayList<>(jarFiles.length);
            for (final File file : jarFiles) {
                list.add(getArtifactFromFileName(artifactType, file.getName()));
            }
            list.sort(Comparator.comparing(Artifact::getName));
            return list.toArray(new Artifact[list.size()]);
        }

        final File[] jarFiles = ResourceUtil.getPluginJarFiles(artifactType.getId());