Applets don’t have to be just isolated box on a web page. They can communicate with a web page in which they are placed. Below is example of how can applet react to URL changes and also cause the changes.
- Possibility to creates anchor which changes the state of an applet, for example selecting a tab in tabbed pane.
- State changes are added to window history, so you can use back and forward buttons.
- No need to reload applet nor web page.
AJAX allows you to change some part of a page without reloading the whole window. But this raises problems of accessibility for search engines and disabled users. However it is easy to combine both of these methods, offering an AJAX version only there, where it is possible. There is no need for the large changes in the code.