Sending response from Jersey web service (HTTP-POST) to the client (Jquery AJAX)

Question

This is a Jersey web service to post data to a server and store it to the database:

@Path("/add")
@POST
@Consumes({ MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML })
@Produces({ MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML })
public Response create(Resource Resource) {
    Response r = null;
    String message = "sucessfully added";
    try {
        r = Response.status(200).entity(message).build();
        ResourceDAO dao = new ResourceDAO();
        dao.createResource(Resource);
    } catch (SQLException e) {
        message = "Exception in creating new Resource " + e;
        r = Response.status(409).entity(message).build();
        e.printStackTrace();
    } catch (RuntimeException e) {
        message = "Exception in creating new Resource " + e;            
        r = Response.status(409).entity(message).build();
        e.printStackTrace();
    } catch (Exception e) {
        message = "Exception in creating new Resource " + e;
        r = Response.status(409).entity(message).build();
        e.printStackTrace();
    }

        return r;

}

Following is an AJAX client that performs the POST call:

$.ajax({
                type : "POST",
                url : "rest/network/add",
                contentType : 'application/json; charset=utf-8',
                dataType : "json",
                data : JSON.stringify(data),
                success : function(msg /*what should be over here instead of msg if I am to receive a response from the server? */) {
                    //alert: displays the response that comes from the server

                }


            });

Issue : Web service has to return the response to the ajax-client and the ajax-client has to display the response in an alert. Response if an exception is encountered(data already exists in the DB) is different from Response when there is no exception.

Question: What are the changes to be made on the server and client side codes so that sending and receiving of responses is possible?

Any help is highly appreciated. Thanks.

Answer 1

Have you tried with

success : function(response) {
                                alert(response.responseText); 
                            },
error : function(jqXHR, textStatus,errorThrown) {

            //here you would print the errorThrown                  

                            }

Answer 2

The web service looks as follows:

@Path("/add")
@POST
@Consumes({ MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML })
@Produces({ MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML })
public Response create(Resource resource) throws Exception {
    Response r = null;
    String message = null;
    System.out.println("in post");
    ResourceDAO dao = new ResourceDAO();

    message = dao.createResource(resource);
    /*this message as a function of createResource: success returns- "Created" exception returns = "Not Created"*/
    r = Response.status(200).entity(message).build();
    return r;

}

The ajax call looks like this:

$.ajax({
                type : "POST",
                url : "rest/Resource/add",
                contentType : 'application/json; charset=utf-8',
                dataType : "json",
                data : JSON.stringify(data),
                statusCode : {
                    200 : function(jqXHR) {
                        $.messager.alert('Request Status',
                                jqXHR.responseText);

                    }

                },


                error : function(jqXHR, textStatus, errorThrown) {
                    $('#createResourceDialog').dialog('close');

                    $.messager.alert('Error',
                            'Unable to connect to the server');

                }

            });

This code works fine. But it executes the

error : function(jqXHR, textStatus, errorThrown) {
                    $('#createResourceDialog').dialog('close');

                    $.messager.alert('Error',
                            'Unable to connect to the server');

                }

every single time - even after executing the statusCode block. This sounds illogical. I expect error block to execute only when the ajax call fails to communicate with the URL/server. Help needed!