jQuery validation with Bootstrap classes, has-error

$.validator.setDefaults({
    errorElement: "span",
    errorClass: "help-block",
    highlight: function (element, errorClass, validClass) {
        $(element).closest('.form-group').addClass('has-error');
    },
    unhighlight: function (element, errorClass, validClass) {
         $(element)
                      .closest('.form-group')
                      .removeClass('has-error')
                      .addClass('has-success');
 }, errorPlacement: function (error, element) {

if (element.parent('.input-group').length || element.prop('type') === 'checkbox' || element.prop('type') === 'radio') { 
error.insertAfter(element.parent()); } 
else { 
error.insertAfter(element); } 
} 
});

References:

https://stackoverflow.com/questions/18754020/bootstrap-3-with-jquery-validation-plugin

https://stackoverflow.com/questions/22483317/jquery-validate-doesnt-add-success-class