rest-http POST method

i want to sent json by post method
after change integration configuration
and write test i send object but response is failed

<int-http:inbound-gateway id="inboundEmployeeSearchRequestGateway" 
        supported-methods="POST"
        request-payload-type="org.springframework.integration.samples.rest.domain.Employee"
        request-channel="employeeSearchRequest"
        reply-channel="employeeSearchResponse"
        mapped-response-headers="Return-Status, Return-Status-Msg, HTTP_RESPONSE_HEADERS"
        path="/services/employee/{id}/search"
        reply-timeout="50000"  
        >

@Test
    public void testGetEmployeeAsJsonPOST() throws Exception {
        Map<String, Object> employeeSearchMap = getEmployeeSearchMap("0");

        final String fullUrl = "http://localhost:8080/rest-http/services/employee/{id}/search?format=json";
        HttpHeaders headers = getHttpHeadersWithUserCredentials(new HttpHeaders());
        headers.add("Accept", "application/json");
        Employee em=new Employee(6, "ali akbar", "azizkhani");
        HttpEntity<Employee> request = new HttpEntity<Employee>(em,headers);
        ResponseEntity<?> httpResponse = restTemplate.exchange(fullUrl, HttpMethod.POST, request,EmployeeList.class, employeeSearchMap);
        logger.info("Return Status :" + httpResponse.getHeaders().get("X-Return-Status"));
        logger.info("Return Status Message :" + httpResponse.getHeaders().get("X-Return-Status-Msg"));
        assertTrue(httpResponse.getStatusCode().equals(HttpStatus.OK));
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        jaxbJacksonObjectMapper.writeValue(out, httpResponse.getBody());
        logger.info(new String(out.toByteArray()));
    }

Start with the rest-http integration configuration and the testGetEmployeeAsJsonPOST test shown in the issue. Reproduce the JSON POST request and inspect the response and related comments to identify whether the failure is in request mapping, payload conversion, or the test setup. Done means the request succeeds with a documented regression test.