I have a PHP web application environment. I am using Slim Framework as REST interface for my application. My application front-end is written using Backbone.js and jQuery.

There is a utility (.jar file) which when I use command line makes a remote call (I guess this is a Web Service) which returns me the data.

how do I best incorporate this into my webapplication described on top?

My application front end will have a Button that should make an AJAX call to the REST Interface and fetch the data as JSON.

My approach: PHP-REST interface url is: /api/phprestapi.php exists

Add a JAVA-REST interface at url: /api/javarestapi.java (Perhaps) to separate these two

Existing Environment: LAMP Stack on Ubuntu

How do I achieve this? What is the kind of effort involved?

Thanks for your pointers