public <T> void post(String url, Header header, Query query, Object body, Type responseType, Callback<T> callback) {
        execute(url, HttpMethod.POST, new RequestHttpEntity(header, query, body), responseType, callback);
    }
@Test
    void testPost() throws Exception {
        restTemplate.post(TEST_URL, Header.EMPTY, Query.EMPTY, "body", String.class, mockCallback);
        verify(requestClient).execute(any(), eq("POST"), any(), any(), eq(mockCallback));
    }