Get json data from angularjs http post request thanks to servlet - json

Question

I try to send data in JSON format from angularJS client thanks to post http request and get it thanks to j2ee servlet. But I meet a mistake. My complete data can be access thanks to getParameterNames method in my servlet and I can't get it in other way.
I don't understand why my data is the Key and not a value.
AngularJS Client
setParametersForTools : function (toolName, data) {
var jsonData = JSON.stringify(data) // I try with json and stringify json
var promise =
$http({
url: configuration.root_url_api+"SetParametersServlet?tool="+toolName,
method: "POST",
dataType: 'json',
data: data,
headers: {'Content-Type': 'application/x-www-form-urlencoded'}
})
.then(function (response){
console.log(response);
}, function (error){
console.log(error);
})
return promise;
}
Servlet
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String toolname = request.getParameter("tool"); //toolname is correct
String json = request.getParameter("data"); // return null...
Enumeration<String> paramsName = request.getParameterNames();
for (;paramsName.hasMoreElements();) {
String paramName=paramsName.nextElement();
System.out.println("param:"+paramName);
}
}
Servlet log
//For Parameter names
param:tool
param:{ my correct data in json format}
Maybe I don't send data correctly but after many searches I don't understand what's wrong.

Answer 1

Please make the following changes in your code.
setParametersForTools : function (toolName, data) {
$http.post(configuration.root_url_api+"SetParametersServlet?tool="+toolName, data)
.then(function (response){
console.log(response);
}, function (error){
console.log(error);
});
}

Answer 2

If you want to use json I'd suggest to implement JAX-RS service instead of Servlet, it will be much easier, especially if you will later use some more complex json.
Pseudo code for service (you will need to add jax-rs configuration to web.xml also):
#Path("/myPath")
public class MyService {
#POST
#Produces(MediaType.APPLICATION_JSON)
#Consumes(MediaType.APPLICATION_JSON)
public OutputData setParameters(InputData data, #QueryParam("tool") String tool) {
System.out.println("Input data: " + data);
System.out.println("Tool name: " + tool);
...
return outputData;
}
}
where inputData and outputData are Java objects representing json.

Answer 3

I found a good answer with this post.
$httpParamSerializer method fixes the problem