Get all radio button values in page load

Get all radio button values in page load

My code :

<input type="radio" class="radioBtnClass" value="1" />1<br/>
<input type="radio" class="radioBtnClass"  value="2" />2<br/>
<input type="radio" class="radioBtnClass" alue="3" />3<br/>


$(document).ready(function(){ 
            $('.radioBtnClass').each(function(){
alert($(this).val());
});
});
All alerts shows empty.
How to get this all radio values in page load?Is it possible?