Jquery serialize & #RequestBody not working - jackson

Question

Well I have gone through most of the questions regarding this topic in SO but not able to fix this issue.
My question is whenever I am using #RequestBody annotation within the below controller method, the ajax call never invokes this method but if I remove the #RequestBody annotation, the control comes in the method but having null values for contact object: Why the serialized form is not getting bind to the object?
and getting error: The request sent by the client was syntactically incorrect
controller:
#RequestMapping(value="/addContacts.htm", method = RequestMethod.POST, headers = {"content-type=application/json"})
#ResponseBody
public String addContacts(#RequestBody Contact contact, HttpServletRequest request ) {
return "success";
}
ajax call:
$("#add_more_contact").click(function(){
var formJson = $("#addContactForm").serialize();
$.ajax( {
url : "/myproject/admin/addContacts.htm",
type : "POST",
data : formJson,
dataType : "text",
contentType : "application/json",
success : function(data) {
alert('Success - '+data);
},
error : function(xhr, desc, err) {
alert("Desc: " + desc + "\nErr:" + err);
}
});
});
POST data in ajax request: these 4 variables are present in my Contact object.
firstName=bill&lastName=gates&email=&mobileNumber=
project-servlet.xml:
<bean id="jacksonMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
<property name="supportedMediaTypes" value="application/json"/>
</bean>
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<ref bean="jacksonMessageConverter" />
</list>
</property>
</bean>
<mvc:annotation-driven/>
Using jackson jar : jackson-all-1.9.9.jar
Not sure what I am missing??Any help will be highly appreciated.

Answer 1

The HTTP 400 Bad Request (The request sent by the client was syntactically incorrect) error occurs when the client did not send a syntactically correct entity.
In this case, the request body is expected to be a valid json, but it wasn't. As #Dave mentioned, your request does not contain a JSON, but a urlencoded string such as name=stack&value=overflow. Instead, it should be a JSON, such as {"name":"stack", "value":"overflow"}.
To achieve this, please refer to another good thread : Convert form data to JavaScript object with jQuery .
A possible fix of your code:
$("#add_more_contact").click(function(){
var formJson = $("#addContactForm").serializeToObject(); // use plugin, or build by yourself
// this variable should be a javascript object,
// such as {"name":"stack", "value":"overflow"}
$.ajax( {
url : "/myproject/admin/addContacts.htm",
type : "POST",
data : JSON.stringify(formJson), // serialize javascript object to JSON 'string'
dataType : "json", // 'text' -> 'json'
contentType : "application/json", // this can be omitted
success : ...,
error : ...,
});
});

Answer 2

You're serializing as form data not json ... Build an anonymous map of your form data and pass that