Root Element missing in json output

mcvr

Hi,

I am unable to populate my dataTables due to the missing 'root' element.

Please see below code and help me how to fix it.

Piece 1:

  $('#example').DataTable({
       //"ajax": "density.txt",
       "ajax" : "getProductPropData",
       "dataType": 'json',
       "contentType": "application/json; charset=utf-8",
        "columns": [{
            "data": "densityId"
        }, {
            "data": "densityDescription"
        }, {
            data: null,
            className: "center",
            defaultContent: '<a href="#" id="edit" class="edit" data-toggle="modal" data-target="#myModal">Edit</a> / <a href="#" id="delete">Delete</a>'
                //defaultContent: '<button type="button" class="btn-default" data-toggle="modal" data-target="#myModal">Open Modal</button>'
        }]
    });

Piece 2: What I am in in my Struts 2 action class.

public String execute() throws Exception {

        SessionFactory sf = (SessionFactory) ctx.getAttribute("SessionFactory");
        ProductPropertyDAO pdao = new ProductPropertyDAOImpl(sf);
        List<DensityGroup> dg = pdao.getProductPropListData("Density");

        List<DensityGroup> list = new ArrayList<DensityGroup>();
        System.out.println("SIZE is: " + dg.size());

        for (int i = 0; i < dg.size(); i++) {
            DensityGroup denpojo = new DensityGroup();
            denpojo.setDensityId(dg.get(i).getDensityId());
            denpojo.setDensityDescription(dg.get(i).getDensityDescription());
            list.add(denpojo);
        }
        
        data = list;
        
        System.out.println("JSON is :\n" + data);
        return "success";
    }

---

My JSON Data from Chrome Network tab is:

[{"densityDescription":"16 KG","densityId":"21"},{"densityDescription":"Chitti","densityId":"22"}]

Correct data should be:

{"data" : [{"densityDescription":"16 KG","densityId":"21"},{"densityDescription":"Chitti","densityId":"22"}]}

Edited by Allan - Syntax highlighting. Details on how to highlight code using markdown can be found in this guide.

kthorngren

Looks like you might need to use the ajax.dataSrc. Similar to the second example:
https://datatables.net/reference/option/ajax.dataSrc#Examples

You might not need the dataType and `contentType. But if you do then you need change the format from this:

"ajax" : "getProductPropData",
"dataType": 'json',
"contentType": "application/json; charset=utf-8",

Place all your ajax options in an object like this:

"ajax" : {
  "url": "getProductPropData",
  "dataType": 'json',
  "contentType": "application/json; charset=utf-8",
  dataSrc: ''
},

Kevin

edited by Allan - I've added the ajax.dataSrc option to the example for clarity.

mcvr

Lovely, that solved my problem. Thanks a lot.