I need help with following scenario:

I have a XML file wherein the parameters of different pop-up windows are stored(height,width,left,top).

Now I open a pop-up window from my JSF by calling a Javascript function.When I call that JS function, values are forwarded from XML file to the Javascript. There will be multiple pop-ups on a single page.

Now the User can change the position and size of the pop-ups and clicks a "Save settings" button on the Pop-up.When the user clicks, the new coordinates will be saved into the XMl so that whenever he opend that pop-up it opens in the new location with new coordinates.

Can you guys please help me out in this. How should I proceed ?

1. Should I use AJAX for this such that AJAX reads the coordinates from XML files and updates it ?

2. Or JSF reads the values from XML file using a Backing Bean and then forwards these values to Javascript. Similarily when I need to write values to XML, Javascript forwards these values to JSf and JSF calls the Bean which updates in XML.

Please help me out in this.