CODEWITHSUNDEEP
javascriptjqueryhttpservlets
pier92
pier92

Reputation: 397

HTTP Servlet set data response and check it via Javascript

I've a web-app base on HTTP servlet. This is JS request to my servlet:

        $.ajax({
              type:    "POST",
              url:     url,
              xhrFields: {
                  withCredentials: false
               },
              data:{
                  "action"      : action_type,
                  "fingerprint" : fingerprint,
                  "user_id"     : user_id,        

              },
              success: function(data) {

                alert('sdp inviato!');

             },
              // vvv---- This is the new bit
              error:   function(jqXHR, textStatus, errorThrown) {
                    console.log("Error, status = " + textStatus + ", " +
                          "error thrown: " + errorThrown
                    );
              }
            });

This is my servlet code:

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


String action= request.getParameter("action");

UtenteModel um= new UtenteModel();
SDPLineModel sdpmodel= new SDPLineModel();

     if (action.equals("CheckFingerprint")) {

        String fingerprint = (String) request.getParameter("fingerprint");

        String user_id = request.getParameter("user_id");

        SDPLines sdpline = sdpmodel.findFingerprintNew(fingerprint, user_id);

        if (sdpline == null) {

            String message = "Fingerprint non valida!";

            System.out.println("Fingerprint not found! ");

        }
        else {

            System.out.println("Fingerprint found! ");
        }
    }

My question is: can anyone show me some example for modify my servlet and js code, setting a specific response data (for the two case, fingerprint found or not found) and how to check its value via JS code in success:function(data)?

Upvotes: 0

Views: 981

Answers (1)

PacMan
PacMan

Reputation: 1358

if i understand very well your issues is that you want to show the response coming from your servlet to the client trough JS code !! you can try this :

if (sdpline == null) {
    String message = "Fingerprint non valida!";
    response.getOutputStream().print(message);
}else {
    String message = ""Fingerprint found! ""
    response.getOutputStream().print(message);
}

so now in your AJAX request you will get that message in case your request was successfully done . 

},
 success: function(data) {
     alert('message coming from your servlet is '+data);
     //here data will contain one of the messages depending on the if statement 
},

Upvotes: 5

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