public static String decodeQueryParam(final String value) {
        return URLDecoder.decode(value, StandardCharsets.UTF_8);
    }
@Test
    public void testDecodeQueryParam() {
        assertEquals("a=1&b=2", HttpParamConverter.decodeQueryParam("a%3d1%26b%3d2"));

        assertThrows(IllegalArgumentException.class, () -> HttpParamConverter.decodeQueryParam("a%3d1%26b%3d2%%"));
    }