使用Jackson框架的@RequestBody注释的Spring Boot ObjectMapper

Question

Hy guys.

I have some data, given by a jQuery DataTable, that I send to a Spring Controller using Ajax and the data elements. More specifically, the ajax function fragment is:

$.ajax({
                        url: "../todaydatarecover.json",
                        type: "post",
                        data: dataToSend,

As explained me in another post here on Stack, I used (cause the presence of "data") the RequestBody annotation in my controller:

@PostMapping(value="/todaydatarecover.json")


@ResponseBody
    public ModelAndView todayInfoAndIdRecover(ModelAndView model, HttpServletRequest request,
            @RequestBody TodayData todayData) throws IOException
    {   

and, always as explained me, I make a class that have the variables that are sent by ajax to controller; in method sign, you can se that her name is TodayData. This is the implementation:

public class TodayData 
{
    private long dateInBox;
    private String nameInBox;
    private String typeInBox;

<follow setters and getters>

Searching on the web, I found that an explicit setting for object mapper may be requested; so, I found for my configuration (Spring Boot and Jackson Framework, both on last version) this one:

@Bean
     public MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter() {
      MappingJackson2HttpMessageConverter jsonConverter = new MappingJackson2HttpMessageConverter();
      ObjectMapper objectMapper = new ObjectMapper();
      objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
      jsonConverter.setObjectMapper(objectMapper);
      return jsonConverter;
     }

that is putted in the public class MvcConfiguration extends WebMvcConfigurerAdapter file.

The data are passed to Controller as an Object:

$('#eventsdatageneral').on('click', '.btn.btn-info', function(event) 
            {
                var today_date = new Date().getTime(); 
                var dataToSend = new Object();
                dataToSend.dateInBox= today_date;
                dataToSend.nameInBox = host_name;
                dataToSend.typeInBox = type_name;

The problem is that when I click on the button that must enable sending, I got a 404 error.

The object seems well formatted; on console, I got this:

And the parametr seems right:

I got no errors on Java console;

So, what I don't understand is if i wrong the Object Mapper configuration or depends on what I implements on my controller, or other.

Answer 1

You need to do some changes in your code

1. You need to create JSON object as below in order to bind it with your Java POJO class TodayData :

   $('#eventsdatageneral').on('click', '.btn.btn-info', function(event) { var today_date = new Date().getTime(); var dataToSend = {}; dataToSend["dateInBox"] = today_date; dataToSend["nameInBox"] = host_name; dataToSend["typeInBox"] = type_name;

2. While sending your ajax request you need to use JSON.stringify function which will convert your javascript object to JSON.

   $.ajax({ url: "../todaydatarecover.json", type: "post", data: JSON.stringify(dataToSend),

3. Also as alfcope mentioned, ModelAndView and @ResponseBody shouldn't be used together, because when we use @ResponseBody on a method, we are saying that we do not want a view to be produced and the object will be returned as part of your response body.

4. Check the url-pattern in configurations you've done for this application, or correct the url which you are sending as .json .

Answer 2

You are using @RequestBody what means your controller is expecting a payload, so you need to serialise your JavaScript object using JSON.stringify before sending it, otherwise it is going to be sent as url form enconded.

$.ajax({
  url: "../todaydatarecover.json",
  type: "post",
  data: JSON.stringify(dataToSend),
  ...
});

Also, your request mapping looks wrong. You are returning a ModelAndView but using @ResponseBody . They should not be used together and it does not make sense return a ModelAndView to an ajax request.

I suggest you to remove extensions ( .json ) from your request mappings. It should be only:

@PostMapping(value="/todaydatarecover")