Unable to get payload data from post ajax multipart request and request parameters from servletFileUpload.parseRequest(request)

Question

i'm sending an ajax request using javascript using XMLHttpRequest but the parameters

"_mname=abc&code=1"

sent to the servlet does not getstored on fileItems ie

List<FileItem> fileItems = servletFileUpload.parseRequest(request);

when i iterate over fileItems and print it nothing is printed. i'm sending it using multipart/form-data because i will add fileupload later. but currently only sending parameters(form parameters this is only a snippet) how can i make it to accept the parameters that i send and then recieve it on the servlet i strictly want to use this servlet and don't want create other one (although suggestions are welcome)

when i send a normal multipart request the servlet runs properly without any problems but not the same in case of ajax request

i'm unable to set

requestObject.setRequestHeader("Content-length",param.length); requestObject.setRequestHeader("connection","close");

it gives me error 405 unsafe operation what is the reason and is it necessary while sending ajax request? i also want to send request using multipart/form-data. is ajax request sent correctly by me? is there any problem with the servlet? how can i read the payload in the servlet? please guide where i might be possibly wrong?

here's the code

    var requestObject = null;
    function createRequestObject(){
        try{
            requestObject = new XMLHttpRequest();
        }
        catch(e){

            try{
                requestObject = new ActiveXObject("Msxml2.XMLHTTP");
            }
            catch(e){
                try{
                    requestObject = new ActiveXObject("Microsoft.XMLHTTP");
                }
                catch(e){
                    alert("update your browser");
                }
            }
        }
        return requestObject;
    }

    function sendAjaxRequest(){
        var requestObject = createRequestObject();
        if(requestObject){
            requestObject.open("POST","personaldetails.do",true);
            var boundary = "----rrrrrr----";
            requestObject.setRequestHeader("Content-type","multipart/form-data; charset=utf-8; boundary=" + boundary);
            //requestObject.setRequestHeader("Content-length",param.length);    //when this line is opened it gives 405 error refused unsafe operation what is the reason form the error?
            //requestObject.setRequestHeader("connection","close");     //when this line is opened it gives 405 error refused unsafe operation what is the reason form the error?
            requestObject.onreadystatechange = sendRequest;
            requestObject.send("_mname=abc&code=1");
        }
    }
    function sendRequest(){
        if(requestObject.readyState == 4 && requestObject.status == 200){
            if(requestObject.responseText){
                console.log("update successfull");
            }
        }
    }


    public class PersonalDetailsServlet extends HttpServlet{
        public void doPost(HttpServletRequest request,HttpServletResponse response) throws IOException,ServletException{

        if(ServletFileUpload.isMultipartContent(request)){
            System.out.println("request is multipart");

            DiskFileItemFactory diskFileItemFactory = new DiskFileItemFactory();
            ServletFileUpload servletFileUpload = new ServletFileUpload(diskFileItemFactory);

            try{
                List<FileItem> fileItems = servletFileUpload.parseRequest(request);
                System.out.println(pds+"fileItems :"+fileItems);

                for(FileItem fileItem : fileItems){
                    System.out.println("fieldname :"+fileItem.getFieldName());
                    System.out.println("inside for loop");
                    field = fileItem.getFieldName();
                    if(fileItem.isFormField()){
                         if(field.equals("_mname")){
                            motherName = fileItem.getString().trim();
                            System.out.println(pds+"mother name :\t\t>"+motherName+"<");

                        }else if(field.equals("code")){
                            code = fileItem.getString().trim();
                            System.out.println(pds+"code :\t\t>"+code+"<");

                            if(code.equals("1")){
                                flag = true;
                                System.out.println("ajax request recieved");
                            }
                        }

                    }else {
                        System.out.println("file for upload recieved");
                    }
                }//for loop end
            }catch(FileUploadException e){
                e.printStackTrace();
            }catch(Exception e){
                e.printStackTrace();
            }
        }
    }