Java script in The "Hello, World" of Google Maps

[jite eghagha]

The hello world of Google Maps is straight forward.

But, I want to have several users interacting on the "one" map.

So that if one user places a marker at a lat/lng, that change reflects on all users; and if one user is tracking a cars movment, that movement shows on all my users maps.

I want to host the "one" true map on my server that will propagate all changes to all users.

How do i use java scripts on the server side of a Java web application? How do i make the client sided "hello world", a server sided "hello world"

      
<script src="http://maps.google.com/maps?file=api&v=2&key=abcdefg&sensor=true_or_false"  type="text/javascript"></script>    
<script type="text/javascript">    
function initialize() {      
if (GBrowserIsCompatible()) {        
var map = new GMap2(document.getElementById("map_canvas"));        
map.setCenter(new GLatLng(37.4419, -122.1419), 13);        
map.setUIToDefault();      
}    
}    
</script>  

The "hello world" of google maps

google maps "Hello World"

[Ulf Dittmer]

On a very fundamental level, that will require the "master" map to communicate any noteworthy changes back to the server (most likely using an AJAX library like Prototype or jQuery), then a server component that accepts these changes (maybe a servlet), and finally all other map instances must check with the server every so often if there's anything new, also using AJAX or maybe Comet.