assertThat(traverser.isExistClass(TestCase.class.getName()), is(not(true)));

        final Set<String> set = new HashSet<String>();
        traverser.forEach((ClassHandler) (packageName, shortClassName) -> set.add(ClassUtil.concatName(packageName, shortClassName)));
        assertThat(set.size() > 0, is(true));
        assertThat(set.contains(DummyTest.class.getName()), is(true));
        assertThat(set.contains(TraverserUtilTest.class.getName()), is(true));

        ClassTraversalUtil.forEach(con.getJarFile(), (ClassHandler) (packageName, shortClassName) -> {
            if (count < 10) {
                System.out.println(ClassUtil.concatName(packageName, shortClassName));
            }
            assertThat(packageName, is(notNullValue()));
            assertThat(shortClassName, is(notNullValue()));
            assertThat(packageName,

        assertThat(ClassUtil.concatName("aaa", "bbb"), is("aaa.bbb"));
        assertThat(ClassUtil.concatName("aaa", null), is("aaa"));
        assertThat(ClassUtil.concatName("aaa", ""), is("aaa"));
        assertThat(ClassUtil.concatName(null, "bbb"), is("bbb"));
        assertThat(ClassUtil.concatName("", "bbb"), is("bbb"));
        assertThat(ClassUtil.concatName("", "bbb"), is("bbb"));

        for (final File file : dir.listFiles()) {
            final String fileName = file.getName();
            if (file.isDirectory()) {
                traverseFileSystem(file, ClassUtil.concatName(packageName, fileName), handler);
            } else if (fileName.endsWith(".class")) {
                final String shortClassName = fileName.substring(0, fileName.length() - CLASS_SUFFIX.length());