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HTML page using local data not showing changes to local data immediately

I am fairly new to web development. I am using HTML and Javascript, specifically the Jexcel Javascript library, to create a spreadsheet webpage. The spread sheet is sourced from a CSV file stored in the working directory of my project. The problem is, when I make changes to that CSV file, they do not show up in my project until I rename the file (and change the filepath in my code respectively). I suspect this has to do with the webpage caching the source CSV file, but I am not sure. How would I go about disabling caching/making my table source from the CSV file everytime? I am using Tomcat Web Server as well. Thank you.
The code that is sourcing my spreadsheet is the following:
<script>
$('#spreadsheet').jexcel({
allowInsertRow: false,
allowInsertColumn: false,
allowDeleteRow: false,
allowDeleteColumn: false,
csv : 'data/test.csv',
csvHeaders : true,
defaultColWidth : '200px',
});
</script>
When changes are made to test.csv I want those changes to show the next time the page is refreshed, but this is not currently happening.
Update: Restarting the Web Server does make the changes show up, so I believe this is a caching issue. I am using Java Servelets on the Server Side of my code.

Browser side caching of resources is a common issue.
To prevent it, the easiest way is to append a version hash to resource url to force reload when modified, so you still benefit of cache feature when file hasn't changed.
Without information about the languages you use on server side, it's very difficult to help you more.
Here is the fonction I generally use to generate resources url :
function assetv($path) {
$hash = 'undefined';
if (file_exists($path)) {
$hash = filemtime($path);
if (!$hash) {
$hash = md5_file($path);
}
}
return urlFromPath($path) . "?v=" . $hash;
}
Of course, the "urlFromPath" depends on your app ;-)
[EDIT]
The browser loads your csv file using an url (data/test.csv) that is "used as cache key" (approximately).
So to force reload when file was modified, you need to change the url, for instance with a version number parameter (file name doesn't changes) :
data/test.csv?v=1
data/test.csv?v=2
As server side only is aware of file state, you need to generate the versionned url on server side when building your HTML.
Finally, instead of managing a version number manually, you can use a "natural" attribute of the file, as it's last modification time or a hash of it's content.

Thank you all for the suggestions. Ultimately I found out the problem was due to the fact that the csv file I was sourcing my data from was in the project folder and Tomcat does not update changes to that file immediately. I solved this by reading the data from a file stored outside the working directory on my machine.

Javascript: Save uploaded file

I would like to save uploaded file using javascript, in my linux server. The code I wrote is:
if (uploadInput.files.length == 0) {
console.log("No file is uploaded. ");
} else {
console.log("File uploaded.");
var file = uploadInput.files[0];
}
Now I would like to save that file as "files/upload.csv". Can anyone please advise, how can I do it?
Thanks in advance

What I'm going to do is walk you through the logic, instead of providing code. There is just not enough information here on what you want to do to provide actual code and the sample you provided is a very small part of what the actual solution would need to include.
I'm assuming the code you wrote above is meant to run on a website visitor's browser (client-side). Client-side code can't save to a server. What it can do, is send the file contents to the server. But then you'd need something on the server side to process that file contents and actually save it to the server-side files directory.
One method to send the file contents from the client to the server is to use AJAX - you can do this with native javascript, but I would recommend looking into a library such as Jquery, which makes it a lot easier. See http://api.jquery.com/jquery.ajax/ This AJAX code will need a communication point on the server to send the file contents to. From your profile it seems you're familiar with PHP. You could make a php file on the server (say receivefilecontents.php) that takes in input from that client-side AJAX call, and then saves it to a server directory - you could also do this in Python, Java or a number of other languages.

How can i read local file from D drive in javascript

My requirement is to read the json file which contains some data and store in some other .js file.
I got task to read local file from local disk in Javascript , i have used file path like - D:\json\analytics.json.
(document).ready(){
($).getData("D:\json\analytics.json");
}
when i see in firebug it takes other url.
How I can do it, is it possible to read file from javascript.
I don't know javascript , i have seen some answer but i am not able to understand .
Need Solution , how I can achieve it. is there any other way to read file on jsp without using scriptlet . From server side , can send it on the jsp page.

I think Jaronmanda's answer won't work cause it will hit cross origin issue, see "Cross origin requests are only supported for HTTP." error when loading a local file.
As the page suggested, in general you need to serve that json file from a web service (same domain, or allow your domain to access), but it depends on what you really need to do. If you can control where that json file is stored, the easier way is to put that in a subdirectory of your html file, and do:
$(document).ready(function () {
$.get('<directory>/analytics.json', function (data) {
// Do your stuff
});
});

Write text file using acrobat javascript

Trying to write to a text file w/ Adobe Acrobat Reader utilizing AcroJS.
As a concept I got how to use trusted functions in Acrobat but when I tried to run following example to save (different problem then the original) the pdf form under a different name using this.saveAs(..) received an error.
My question is two fold;
1- Why do I get "Security settings prevent access to this property or method" error and how do I get rid of it?
trusted function in javascript folder is as follwos (copeid off the web)
var mySaveAs = app.trustedFunction( function(cFlName)
{
app.beginPriv();
try{
this.saveAs(cFlName);
}
catch(e){
app.alert("Error During Save " + e.message );
}
app.endPriv();
});
I am calling the trusted function from the doucment as follwos and expecting a file with the name sample.pdf will be generated inside "C:/test"
if(typeof(mySaveAs) == "function")
{
mySaveAs("/C/test/sample.pdf");
}
else
{
app.alert("Missing Save Function");
}
2- How do I write to a text file? Here I want to extract some field values from the PDF form and write those into a text file (or XML)!

As you might have guessed, it's a security measure to prevent malicious scripts from causing havoc. You'll need to turn down the security settings. To do this, Ctrl+K into Preferences, go to the Enhanced Security tab and disable it.
For addition information on Enhanced Security, refer to: http://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/enhanced.html
As far as I know, there aren't any functions that will allow you to write arbitrary data to a text file or XML file. However, you have a couple of options:
Use Doc.exportAsText (text) and Doc.exportAsFDF (XML) to export data from carefully crafted fields. This isn't very straightforward and a little awkward, but it works.
Use Net.HTTP.request or Net.SOAP to send data to an ad-hoc local web server (eg: something simple, running Python or PHP) and let them handle the request. This allows you to do pretty much anything you want, but requires more work to setup the server.
See: Acrobat JS API Reference

Reading local XML file with javascript

I am new to HTML/Javascript, as well as coding in general so bear with me :). I am trying to create a "Spot the Difference" game in html5 using javascript. Everything is local (on my machine). I have two pictures, of the same size, one with differences. To generate data about the clickable fields, I have a java program that reads both of the images and outputs all of the positions in which pixels are different into a XML file. My plan was to then use this XML file with my javascript to define where the user could click. However, it appears (correct me if I'm wrong) that javascript cannot read local XML files for security reasons. I do not want to use an ActiveXObject because I plan on putting this onto mobile devices via phone gap or a webkit object. Does anyone have a better approach to this problem, or perhaps a way to read local XML files via javascript? Any help would be greatly appreciated, thanks.

If you are planning to put this into a smart phones (iOS and Android) and read local files, I have done similar things with JSON (yes, please don't use XML).
Convert your output to JSON
Put this as part of your application package. For example, in Android, I put it as part of the .apk in /appFiles/json
Create a custom content provider that would read the local file. I create mine as content:// but you create whatever scheme you want. You could leverage android.content.ContentProvider in order to achieve custom URL Scheme. iOS has its own way to create custom scheme as well. The implementation simply read your local storage and give the content
To read it from Javascript, I simply call ajax with the custom scheme to get the json file. For example content://myfile/theFile.json simply redirect me to particular directory in local storage with /myfile/theFile.json appended to it
Below is the sample to override openFile() in the ContentProvider
public ParcelFileDescriptor openFile (Uri uri, String mode) {
try {
Context c = getContext();
File cacheDir = c.getCacheDir();
String uriString = uri.toString();
String htmlFile = uriString.replaceAll(CUSTOM_CONTENT_URI, "");
// Translate the uri into pointer in the cache
File htmlResource = new File(cacheDir.toString() + File.separator + htmlFile);
File parentDir = htmlResource.getParentFile();
if(!parentDir.exists()) {
parentDir.mkdirs();
}
// get the file from one of the resources within the local storage
InputStream in = WebViewContentProvider.class.getResourceAsStream(htmlFile);
// copy the local storage to a cache file
copy(in, new FileOutputStream(htmlResource));
return ParcelFileDescriptor.open(htmlResource, ParcelFileDescriptor.MODE_READ_WRITE);
} catch(Exception e) {
throw new RuntimeException(e);
}
}
I hope it helps

I would suggest modifying your java program to output a JSON formatted file instead of XML. JSON is native to JavaScript and will be much simpler for you to load.
As for actually loading the data, i'm not sure what the best option is as you say you want to evenutally run this on a mobile device. If you were just making a normal website you could setup a web server using either Apache or IIS depending on your OS and put the files in the document root. Once you've done that you can load the JSON file via Ajax, which can easily be googled for.
Not sure if this helps any.

Since this is a local file, you can do this with jQuery
$.ajax({
type: "GET",
url: "your.xml",
dataType: "xml",
success: function(xml){
///do your thing
}
});
http://api.jquery.com/jQuery.ajax/