AJAX功能似乎无法正常工作

Question

我有以下编码，

<script type="text/javascript">  
    $(document).ready(function(){   


        (function ajaxInterval() {
            $.ajax({  
                url:'clmcontrol_livematchupdate',
                type:'post', 
                dataType: 'json',  
                success: function(data) {  


                    $('#lblbattingteam').html(data.battingnow);
                    $('#lblscore').html(data.score);
                    $('#lblwickets').html(data.wickets);
                    $('#lblovers').html(data.overs);
                    $('#lblballs').html(data.balls);
                    $('#lblextras').html(data.extras);
                    $('#lblrr').html(data.runrate);

                    $('#lblbowlingteam').html(data.bowlingnow);
                    $('#lblbowler').html(data.currentbowler);
                    $('#lblbowlerovers').html(data.bowlerovers);
                    $('#lblbowlerballs').html(data.bowlerballs);
                    $('#lblrunsgiven').html(data.runsgiven);
                    $('#lblextrasgiven').html(data.extrasgiven);
                    $('#lblwicketstaken').html(data.wicketstaken);
                    $('#lblecon').html(data.econ);


                },
                complete: function() {
                    // Schedule the next request when the current one has been completed
                    setTimeout(ajaxInterval, 4000);
                }  
            });
        })();
    });  
</script> 

一开始这个工作正常，但经过几次尝试后这不起作用，标签也没有更新，我也没有对servlet进行任何更改。我的servlet如下所示，请帮我解决这个问题。

protected void processRequest(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    HttpSession session = request.getSession();
    response.setContentType("text/json");
    PrintWriter out = response.getWriter();

    try {
        JSONObject json = new JSONObject();
        ResultSet rscurteaminfo = clmmodel_database.selectQuery("select ct.teamname, cm.score, cm.wickets, cm.extras, cm.balls, cm.currentbatsman, cm.currentbowler from clm_match cm inner join clm_team ct on ct.teamid = cm.battingnow where cm.matchid = '" + session.getAttribute("matchid") + "'");
        ResultSet rsbowlingteaminfo = clmmodel_database.selectQuery("select ct.teamname, cm.currentbowler ,cp.playerfname, cpm.ballsbowled, cpm.wickets, cpm.runsgiven, cpm.extrasgiven from clm_match cm inner join clm_team ct on ct.teamid = cm.bowlingnow inner join clm_playerinmatch cpm on cpm.playerid = cm.currentbowler inner join clm_player cp on cp.playerid = cm.currentbowler where cm.matchid = '" + session.getAttribute("matchid") + "'");
        ResultSet rscurbatsmen = clmmodel_database.selectQuery("select cp.playerid, cp.playerfname , cpm.runsscored, cm.currentbatsman from clm_playerinmatch cpm inner join clm_player cp on cp.playerid = cpm.playerid inner join clm_match cm on cm.matchid = cpm.matchid where cm.battingnow = cp.teamid and cpm.currentstate = 'Batting' and cm.matchid = '" + session.getAttribute("matchid") + "'");

        while (rscurteaminfo.next()) {
            //Calculate overs and balls
            int balls = (Integer) rscurteaminfo.getInt("balls");
            int ballsperover = 6;
            int k = balls % ballsperover;
            int overs = 0;

            if (balls >= 6) {

                overs = (balls - k) / ballsperover;
            }

            //Calculate overs and balls   

            double runs = Double.parseDouble(rscurteaminfo.getString("score"));
            double ballshalf = k / 6.0;
            double totalovers = overs + ballshalf;
            double runrate = runs / totalovers;

            double inf = Double.POSITIVE_INFINITY;
            if (runrate == inf) {
                runrate = 0.0;

            }

            json.put("battingnow", rscurteaminfo.getString("teamname"));
            json.put("score", rscurteaminfo.getString("score"));
            json.put("wickets", rscurteaminfo.getString("wickets"));
            json.put("overs", overs);
            json.put("balls", k);
            json.put("extras", rscurteaminfo.getString("extras"));
            json.put("runrate", runrate);


        }

        while (rsbowlingteaminfo.first()) {
            int balls = (Integer) rsbowlingteaminfo.getInt("ballsbowled");
            int ballsperover = 6;
            int k = balls % ballsperover;
            int overs = 0;

            if (balls >= 6) {

                overs = (balls - k) / ballsperover;
            }


            double runs = Double.parseDouble(rsbowlingteaminfo.getString("runsgiven"));
            double ballshalf = k / 6.0;
            double totalovers = overs + ballshalf;
            double econ = 0.0;


            econ = runs / totalovers;

            double inf = Double.POSITIVE_INFINITY;
            if (econ == inf) {
                econ = 0.0;

            }
            json.put("bowlingnow", rsbowlingteaminfo.getString("teamname"));
            json.put("currentbowler", rsbowlingteaminfo.getString("playerfname"));
            json.put("bowlerovers", overs);
            json.put("bowlerballs", k);
            json.put("runsgiven", rsbowlingteaminfo.getString("runsgiven"));
            json.put("extrasgiven", rsbowlingteaminfo.getString("extrasgiven"));
            json.put("wicketstaken", rsbowlingteaminfo.getString("wickets"));
            json.put("econ", econ);


        }

        out.print(json);

    } catch (Exception e) {
        e.printStackTrace();
    }
}