Session Timeout Implementation in JavaScript - particularly useful for mobile and smart (hybrid) clients that have a session management implementation at the server side

timeout-snippet.js

/**********************************************************
 *        SESSION TIMEOUT IMPLEMENTATION FROM JAVASCRIPT  *
 * ********************************************************/
 

function Session() {}

Session.prototype.init = function() {
  console.log('inside Session.init()');

  //capturing all click, touch and keypress events
	window.addEventListener('touchstart',Timeout,false);
	window.addEventListener('click',Timeout,false);
	window.addEventListener('keypress', Timeout, false);

	function _timeout(){
		return function() {
			//implement your logic here to make
      //a server side call (REST maybe?)
      //that kills the server side sessiom
		}	
	}
	function Timeout() {
	console.log('inside goTimeout()');
		if(typeof(timer) != 'undefined'){
			console.log("clearing timer");
			timer = clearTimeout(timer); //reset as soon as something is clicked
		}
		timer = setTimeout(_timeout(), 5000 /*test tiemout period in millisec*/);
	}
}

var sessionTimeout = new Session();
sessionTimeout.init();

timer is undefined.

am using this. brilliant :)