public static boolean checkEmail(String email) {
        if (StringUtils.isBlank(email)) {
            return false;
        }
        EmailValidator emailValidator = new EmailValidator();
        if (!emailValidator.isValid(email, null)) {
            return false;
        }
        // Email is at least a second-level domain name
        int indexDomain = email.lastIndexOf("@");
        String domainString = email.substring(indexDomain);
        return domainString.contains(".");
    }
@Test
    public void testCheckEmail() {
        Assertions.assertTrue(CheckUtils.checkEmail("test01@gmail.com"));
        Assertions.assertFalse(CheckUtils.checkEmail("test01@gmail"));
        Assertions.assertFalse(CheckUtils.checkEmail("test01@gmail."));
        Assertions.assertTrue(CheckUtils.checkEmail("test01@gmail.edu.cn"));
    }