### Question:
JarFinder { public static void jarDir(File dir, String relativePath, ZipOutputStream zos) throws IOException { Preconditions.checkNotNull(relativePath, "relativePath"); Preconditions.checkNotNull(zos, "zos"); File manifestFile = new File(dir, JarFile.MANIFEST_NAME); ZipEntry manifestEntry = new ZipEntry(JarFile.MANIFEST_NAME); if (!manifestFile.exists()) { zos.putNextEntry(manifestEntry); new Manifest().write(new BufferedOutputStream(zos)); zos.closeEntry(); } else { InputStream is = new FileInputStream(manifestFile); copyToZipStream(is, manifestEntry, zos); } zos.closeEntry(); zipDir(dir, relativePath, zos, true); zos.close(); }  static void jarDir(File dir, String relativePath, ZipOutputStream zos); static String getJar(Class klass);  }### Answer:
@Test public void testExistingManifest() throws Exception { File dir = new File(System.getProperty("test.build.dir", "target/test-dir"), TestJarFinder.class.getName() + "-testExistingManifest"); delete(dir); dir.mkdirs(); File metaInfDir = new File(dir, "META-INF"); metaInfDir.mkdirs(); File manifestFile = new File(metaInfDir, "MANIFEST.MF"); Manifest manifest = new Manifest(); OutputStream os = new FileOutputStream(manifestFile); manifest.write(os); os.close(); File propsFile = new File(dir, "props.properties"); Writer writer = new FileWriter(propsFile); new Properties().store(writer, ""); writer.close(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); JarOutputStream zos = new JarOutputStream(baos); JarFinder.jarDir(dir, "", zos); JarInputStream jis = new JarInputStream(new ByteArrayInputStream(baos.toByteArray())); Assert.assertNotNull(jis.getManifest()); jis.close(); }
@Test public void testNoManifest() throws Exception { File dir = new File(System.getProperty("test.build.dir", "target/test-dir"), TestJarFinder.class.getName() + "-testNoManifest"); delete(dir); dir.mkdirs(); File propsFile = new File(dir, "props.properties"); Writer writer = new FileWriter(propsFile); new Properties().store(writer, ""); writer.close(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); JarOutputStream zos = new JarOutputStream(baos); JarFinder.jarDir(dir, "", zos); JarInputStream jis = new JarInputStream(new ByteArrayInputStream(baos.toByteArray())); Assert.assertNotNull(jis.getManifest()); jis.close(); }