Spring form object binding, works when submitted normally. But how to convert to json and use ajax

Question

I have a form when submitted to a controller works fine, the controller signature :

@RequestMapping(value = "/Save", method = RequestMethod.POST)
public ModelAndView save(@ModelAttribute MyDTO myDTO) {}

I have another controller method for handling an ajax request with this signature:

@RequestMapping(value = "/Preview", method = RequestMethod.POST)
public ModelAndView preview(@RequestBody MyDTO myDTO) {}

However submitting the serialized form returns this error : org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "myList[0]" (Class myPackage.dto.MyDTO), not marked as ignorable

The javascript/jquery is :

var json = jq("#dtoForm").serializeObject();
json = JSON.stringify(json);
jq.ajax({
        cache:false,
    type: 'POST',
    url: "${Preview}",
    data:json,
    contentType: "application/json",
    success:  function(data) {          
        previewDialog.html(data);
        previewDialog.dialog('open');
        }
});

What am I missing ? I am confused becuase the form submits fine (the dto is correctly mapped) when not converted json. The dto contains, amongst other things, a list.

Edit if I remove the json = JSON.stringify(json); as suggested by springsource I get a slightly different error (one of the fields in dto is called "title"):

org.springframework.http.converter.HttpMessageNotReadableException: Could not read JSON: Unrecognized token 'til': was expecting 'null', 'true' or 'false'

http://stackoverflow.com/questions/1184624/serialize-form-to-json-with-jquery/3705197#3705197 — NimChimpsky, Sep 22 '11 at 13:57

score 0 · Accepted Answer · edited May 23 '17 at 10:34

In case anyone else has same problem, I got the code from here : http://code.google.com/p/form2js/ included the libs, and changed my code to this :

var json = jq("#dtoForm").toObject(); //the new lib I dl'd from link
json = JSON.stringify(json);
...
//and then to do the same ajax call

However, it is not completely solved as the spring-mvc form creates a hidden form element for each checkbox, which I then delete manually :

delete json._MyBoolean;

A side note, this all seems rather messy - shouldn't spring/jackson be able to convert pojo's to an html form and json in both directions with out all this extra stuff.

(original stack ref to library is here)

Spring form object binding, works when submitted normally. But how to convert to json and use ajax

1 Answers1