Pass values from javascript to Servlet

I'm new bee working on passing below data from jquery to Servlet. Below are my files

javascript:

<script type="text/javascript"> 
function getData(tableName) 
{
    var tableId =tableName+"Table";
    jsonObj = [];
    $(\'#' + tableId + '\').find(\'tbody>tr\').each(function (i) { 
        var $tds = $(this).find('td'), setvilId = $tds.eq(1).text(),setvilNotes = $tds.eq(8).text(); 
        item = {};
        item["id"] = setvilId;
        item["notes"] = setvilNotes;
        jsonObj.push(item); 
    });
    console.log(jsonObj);
    var jsonString =JSON.stringify(jsonObj);
    request(jsonString);
};
</script>

<script type=\"text/javascript\">
function updateNotes () { 
    var editable = true; 
    var editables = $('td[id*=notestd], td[id*=eta]');
    editables.attr('contentEditable', editable);
} 
function request(jsonString) {
    $.ajax({ 
        url: "/updatesetvil", 
        type: "POST",
        data: jsonString, 
        dataType: "text", 
        success: function(){ 
            alert(\"success\");
        }, 
        error:function(){ 
            alert(\"failure\"); 
        } 
    });
};
</script>


Servlet:

public class UpdateSetvil extends HttpServlet {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;

     List<SetvilJsonAttributes> setvilAttrs = new LinkedList<SetvilJsonAttributes>();
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        out.println("Inside servlet");

        // 1. get received JSON data from request
        BufferedReader br = new BufferedReader(new InputStreamReader(request.getInputStream()));
        String json = "";
        if(br != null){
            json = br.readLine();
        }
        System.out.println(json.toString()); // [{"id":"","notes":""},{"id":"18001","notes":"fdafd"},{"id":"8350","notes":"daggda"},{"id":"8056","notes":"gfdagdfa"}]
        // 2. initiate jackson mapper
         ObjectMapper mapper = new ObjectMapper();

         // 3. Convert received JSON to Class
        SetvilJsonAttributes setvilatt = mapper.readValue(json, SetvilJsonAttributes.class);

        // 4. Set response type to JSON
        response.setContentType("application/json");

        setvilAttrs.add(setvilatt);

        for (int i=0;i< setvilatt.size(); i++) {
            System.out.println(setvilatt.get(i).getId());
        }
    }
    private class SetvilJsonAttributes {
        Integer id;
        String notes;
        String eta;

        public Integer getId() {
            return id;
        }

        public void setId(Integer id) {
            this.id = id;
        }

        public String getNotes() {
            return notes;
        }

        public void setNotes(String notes) {
            this.notes = notes;
        }

        public String getEta() {
            return eta;
        }

        public void setEta(String eta) {
            this.eta = eta;
        }

    }
}

Error: java.io.IOException: Error parsing JSON request string

I kindly request anyone to help me on this.I have been stuck and unable to proceed further.