Question

I have a process that I need to follow, I hope this makes sense.

I have a JSP that builds up json data, and sends to a URL. This URL exists, and therefore will be successful.

However, a java based server socket class is listening on a port, and actually picks up the data being sent and processes it. It needs to generate a response for me to receive (ie success or failure codes of what it is going), that I am looking to pick up in the sucess function – but this java socket listener code does not intend on writing this to a JSP or something similar.

Any ideas how the java listener and my success function can meet so I can get the this response.

In my test, I was making the listener code place the response on a JSP and I pick that but, I want a way to not have to place onto a JSP. Is it a case the response (which will be a JSON data) HAS TO actually be served/held within a JSP/PHP/JSON file?

This is my send code below:

$.ajax({    
 type:       "POST",    
 url:        suppliedURL,    
 data:       "jsonData=" + jsonString, // I have already done a json stringify on this. 
 success:    function(data, textStatus, jqXHR) {    
            var jsonJqXHR = JSON.stringify(jqXHR);   
            alert('jsonJqXHR : ' + jsonJqXHR);    
 },    
 error:function (xhr, ajaxOptions, thrownError){    
   alert('Error xhr : ' + xhr.status);    
   alert('Error thrown error: ' + thrownError);    
 },   
 dataType:   "json"                         

});

Answer 1

Javascript running in a browser page has limited communication and interconnection capabilities. One of the things a javascript program running in virtually any browser can do is send out an HTTP request. So the obvious way to get data into a javascript program is via XMLHttpRequest, via the pattern some people call AJAX. This pattern is implemented in the jQuery ajax function.

The Javascript program needs to connect to an HTTP server – that is where the JSP comes in. It is a Java program that can respond to HTTP GET/POST etc. JSP or a similar HTTP-connected programming environment on the server, is necessary to serve data to the javascript program.

The only challenge therefore is moving the data from the Java socket program running on the server to the JSP also running on the server. One simple way to handle it is via a shared database or filesystem.