public static boolean isBase64(CharSequence base64) {
		if (base64 == null || base64.length() < 2) {
			return false;
		}

		final byte[] bytes = StrUtil.utf8Bytes(base64);

		if (bytes.length != base64.length()) {
			// 如果长度不相等，说明存在双字节字符，肯定不是Base64，直接返回false
			return false;
		}

		return isBase64(bytes);
	}
@Test
	public void isBase64Test(){
		assertTrue(Base64.isBase64(Base64.encode(RandomUtil.randomString(1000))));
	}