Can't submit JSON object to JSP

Question

I'm trying to send a JSON object to a JSP to parse. The JavaScript code is:

function sendData(field1, oper1, value1, field2, oper2, value2, field3, oper3, value3){
        var formData = {"field1":field1, "oper1":oper1, "value1":value1, "field2":field2, "oper2":oper2, "value2":value2, "field3":field3, "oper3":oper3, "value3":value3};
        $.post("<%=request.getRequestURL().toString()%>getInfo.jsp", {formData:formData}, function(response){alertHere(response)});
    }

function alertHere(){
        window.alert("Post Successful!")
    }

My submit button is:

<input type="submit" value="SEARCH" name="submit" class="srchbutton" onclick="sendData(document.getElementById('field1').value, document.getElementById('oper1').value>

There are several more fields passed in the JavaScript button on click, I just didn't want to post that long of a line.

When I try to post with text data in the form, my web developer console flashes the path to my JSP really quickly then disappears. It's too fast to see the error. If there's no data, the post is successful, as my alertHere function in $.post() is called correctly. I'm not sure if I'm missing something.

Try to read the error in Chrome's developer tools "ctrl + shift + i" and click Console. It's a pretty good debug view that shouldn't lose information. — John Humphreys, Aug 18 '14 at 19:37
@nikpon we don't know if there's a Servlet that handle the calls. Note that you can have a servlet which URL can be the exact URL for a valid JSP but the servlet will handle the request, not the JSP. — Luiggi Mendoza, Aug 18 '14 at 19:41
have you check the server logs ? what does it say. Did the request reach the server ? — Tito, Aug 18 '14 at 19:43

score 1 · Answer 1 · answered Aug 18 '14 at 20:48

Assuming you have a servlet on the server side which handles the data you are sending from the jsp page you could create a pseudo-class using javascript, then parses it to json and finally sends it to the server. for example:

javascript and jQuery

function SomeClass (){
  this.field1 = $("#field1").val();
  this.oper1 = $("#oper1").val();
  this.value1 = $("#value1").val();
  // etc. for every field you want to send
}

note: i'm assuming every field have an id.

function alertHere(){
   window.alert("Post Successful!")
}

jQuery and ajax

$("#someID").click(function(){
    event.preventDefault(); <-------- if you replace the submit button for a simple button,
                                      you don't need to do this.
    var formData = new  SomeClass();

    $.ajax({
      url:"ServletName", 
      data: JSON.stringify(formData), 
      dataType:"json",
    }).done(function(response){
         alertHere(response);
    });

});

html

<input type="submit" value="SEARCH" id="someID" name="submit" class="srchbutton">

score 0 · Answer 2 · answered Aug 18 '14 at 20:25

Try changing this line of code

$.post("<%=request.getRequestURL().toString()%>getInfo.jsp", {formData:formData}

To

$.post("<%=request.getRequestURL().toString()%>getInfo.jsp", {formData:Json.stringify(formData)}

Not entirely sure if this would work, Just a suggestion.

score 0 · Accepted Answer · answered Aug 18 '14 at 21:21

Figured it out. The problem was that I wasn't passing my "response" to my success function, so:

function alertHere(){
    window.alert("Post Successful!")
}

should have been:

function alertHere(response){
    window.alert("Post Successful!")
}

It was probably posting correctly, but I wasn't getting a success because the response wasn't getting passed.

Can't submit JSON object to JSP

3 Answers3