title: jQuery Ajax call returns xhr.status = 0 and thrownError = undefined
body: <p>Hi I have read through all the related topic and tried most of the solutions but I still have the problem. 
  I am using a ADF JSF page and have links against each row of a af:table. OnClick, I call a function and pass the selected value and set it as hidden. Then with jQuery, I call ajax and pass the hidden  value. My ajax servlet gets called and I return a Json object. But the ajax throws undefined error and nothing happens. 
  Here's my code</p>
  
  <pre><code>  $(document).ready(function(){                    
        $(".modal").click(function() {
           $.ajax({                             
               url : '/CCA/ajax',
               cache: false,
               data:{ 
                  custnumvalue: '404', // hardcoding for now
                  methodcallname: 'showVehicleDtls'},
               method: 'POST',
               dataType: 'json',
               contentType: "application/json; charset=utf-8",
               success : function(json) {
                  if(!(json.Error == 'true')){
                     populateVehicles(json); 
                  }else if(json.Error == 'true'){
                     alert(json.ErrMsgs);
                  }
               },
               error:function (xhr, ajaxOptions, thrownError){
                  alert(xhr.status);
                  alert(thrownError);
               }                                
            });                            
        });      
  
      }); 
  // this function is called onClick()   
  function setCustValue(cval){
     $("#myForm\\:hideOut").val(cval);
  }
  </code></pre>