RestTemplate POST with JSon - resttemplate

Question

once again iam looking a for help/guide from experts,
My problem is, i need to create Dynamic web site which calls to restfull server to get data, all the requests are POST and returns json object. Iam thinking of use of Spring RestTemplate to make calls to server. My Server works ok, meaning currently some android and Apple apps connects to same APIs and they work ok. But when i try to use RestTemplate to connect to server, it gives some errors
org.springframework.web.client.HttpClientErrorException: 400 Bad Request
this is my server,
#Controller
public class ABCController
{
#RequestMapping(method = RequestMethod.POST, value = "/user/authenticate")
public #ResponseBody LoginResponse login(#RequestParam("email") String email,#RequestParam("password") String password,#RequestParam("facebookId") String facebookId) {
LoginRequest request = new LoginRequest(email, password, facebookId);
UserBusiness userBusiness = UserBusinessImpl.getInstance();
return userBusiness.login(request);
}
}
And this is my spring configs of server,
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:jee="http://www.springframework.org/schema/jee"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd">
<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" />
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />
<bean id="jsonViewResolver" class="org.springframework.web.servlet.view.json.MappingJacksonJsonView" />
<bean id="viewResolver" class="org.springframework.web.servlet.view.BeanNameViewResolver" />
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<ref bean="jsonConverter" />
</list>
</property>
</bean>
<bean id="jsonConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
<property name="supportedMediaTypes" value="application/json" />
</bean>
<bean name="abcController" class="com.abc.def.controller.ABCController" />
<mvc:annotation-driven />
</beans>
This is how i try to call the server using RestTemplate,
<bean id="restTemplate" class="org.springframework.web.client.RestTemplate">
<!-- <constructor-arg ref="httpClientFactory"/> -->
<property name="messageConverters">
<list>
<bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
<property name="objectMapper">
<ref bean="JacksonObjectMapper" />
</property>
</bean>
</list>
</property>
</bean>
<bean id="JacksonObjectMapper" class="org.codehaus.jackson.map.ObjectMapper" />
and this is how i use it (for testing)
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("root-context.xml");
RestTemplate twitter = applicationContext.getBean("restTemplate", RestTemplate.class);
MultiValueMap<String, String> map = new LinkedMultiValueMap<String, String>();
map.add("email", "x1#test.com");
map.add("password", "abc");
map.add("facebookId", null);
HttpEntity<LoginResponse> response= twitter.exchange("https://abc.com/Rest/api/user/authenticate", HttpMethod.POST, map, LoginResponse.class);
my login response class, and its sub classes,
LoginResponse
public class LoginResponse extends BaseResponse {
private LoginBase data;
with getters and setters
}
Login Base
public class LoginBase {
private String token;
private User user;
with getters and setters
}
User
public class User {
private Integer userId;
private String email;
private Integer status;
private String name;
with getters and setters
}
finally BaseResponse
public class BaseResponse {
protected String statusCode;
with getter and setter }
My questions are,
1. Why do i get this error when i call the server
INFO : org.springframework.beans.factory.support.DefaultListableBeanFactory - Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory#63de8f2d: defining beans [restTemplate,JacksonObjectMapper]; root of factory hierarchy
WARN : org.springframework.web.client.RestTemplate - POST request for "https://abc.com/Rest/api/user/authenticate" resulted in 400 (Bad Request); invoking error handler
Exception in thread "main" org.springframework.web.client.HttpClientErrorException: 400 Bad Request
at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:90)
at org.springframework.web.client.RestTemplate.handleResponseError(RestTemplate.java:494)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:451)
2. how do i map json response to java LoginResponse

Answer 1

You might have to add the content-type and accept headers to your request.
Mapping the response to LoginResponse can be done directly like this
LoginResponse lResponse = response.getBody();
or If you are using restTemplate.postForObject(), the reponse will be in the form of LoginResponse