assertArgumentNotNull("jarFile", jarFile);

        try {
            jarFile.close();
        } catch (final IOException e) {
            logger.log(format("ECL0017", e.getMessage()), e);
        }
    }

                                            <label for="jarFile" class="col-md-3 text-sm-right col-form-label"><la:message
                                                    key="labels.plugin_jar_file"/></label>
                                            <div class="col-md-9 text-sm-right col-form-label">
                                                <input id="jarFile" type="file" name="jarFile" class="form-control-file"/>

     *
     * @param jarFile
     *            the Jar file (must not be {@literal null})
     * @param handler
     *            the handler to process resources (must not be {@literal null})
     */
    public static void forEach(final JarFile jarFile, final ResourceHandler handler) {
        assertArgumentNotNull("jarFile", jarFile);
        assertArgumentNotNull("handler", handler);

     * </p>
     *
     * @param jarFile the Jar file (must not be {@literal null})
     * @param handler the handler to process classes (must not be {@literal null})
     */
    public static void forEach(final JarFile jarFile, final ClassHandler handler) {
        assertArgumentNotNull("jarFile", jarFile);
        assertArgumentNotNull("handler", handler);

        if (jarFile.getName().toLowerCase().endsWith(WAR_FILE_EXTENSION)) {

    /**
     * Default constructor.
     */
    public InstallForm() {
        // Default constructor
    }

    /** JAR file containing the plugin to install */
    public MultipartFormFile jarFile;

        for (final WebResource possibleJar : possibleJars) {
            if (possibleJar.isFile() && possibleJar.getName().endsWith(".jar")) {
                try (final JarFile jarFile = new JarFile(possibleJar.getCanonicalPath())) {
                    final Manifest manifest = jarFile.getManifest();
                    if (manifest != null && manifest.getEntries() != null) {
                        final Attributes attributes = manifest.getMainAttributes();

     *
     * @param conn
     *            {@link JarURLConnection}. Must not be {@literal null}.
     * @return {@link JarFile}
     */
    public static JarFile getJarFile(final JarURLConnection conn) {
        assertArgumentNotNull("conn", conn);

        try {
            return conn.getJarFile();
        } catch (final IOException e) {

                    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();

        final Set<String> nameSet = new HashSet<>();
        final File[] jarFiles = ResourceUtil.getPluginJarFiles(PluginHelper.ArtifactType.DATA_STORE.getId());
        for (final File jarFile : jarFiles) {
            try (FileSystem fs = FileSystems.newFileSystem(jarFile.toPath(), ClassLoader.getSystemClassLoader())) {
                final Path xmlPath = fs.getPath("fess_ds++.xml");
                try (InputStream is = Files.newInputStream(xmlPath)) {