} finally {
            System.clearProperty(Constants.FESS_THUMBNAIL_PATH);
        }
    }

    // Test initialization with var path
    @Test
    public void test_init_withVarPath() {
        File varDir = new File(tempDir, "var");
        System.setProperty(Constants.FESS_VAR_PATH, varDir.getAbsolutePath());
        try {
            ThumbnailManager manager = new ThumbnailManager() {