Edit in JSFiddle

+(function ($) {

    "use strict";

    var $window = $(window);
    var $document = $(document);
    var open = false;
    var $navbar = $('.navbar-nav');
    var bsEventName = 'click.bs.dropdown.data-api';
    var bsDropdown = $.fn.dropdown.Constructor;
    var bsClickHandler = bsDropdown.prototype.toggle;

    $navbar.on('mouseenter mouseleave', '.dropdown', dropdownHandler);

    function dropdownHandler(evt) {
        if (evt.type === 'mouseleave') {
            $navbar.find(':focus').blur();
        }

        evt.preventDefault();
        open = evt.type === 'mouseenter';

        $(this).find('[data-toggle=dropdown]').trigger(bsEventName);

        if (open) {
            $document.off(bsEventName, toggle, bsClickHandler);
        } else {
            $document.on(bsEventName, toggle, bsClickHandler);
        }

        return false;
    }
})(window.jQuery);

<nav class="navbar navbar-default" role="navigation">
  <div class="container-fluid">
    <!-- Brand and toggle get grouped for better mobile display -->
    <div class="navbar-header">
      <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">
        <span class="sr-only">Toggle navigation</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </button>
      <a class="navbar-brand" href="#">Brand</a>
    </div>

    <!-- Collect the nav links, forms, and other content for toggling -->
    <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
      <ul class="nav navbar-nav">
        <li class="active"><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li class="dropdown">
          <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown <b class="caret"></b></a>
          <ul class="dropdown-menu">
            <li><a href="#">Action</a></li>
            <li><a href="#">Another action</a></li>
            <li><a href="#">Something else here</a></li>
            <li class="divider"></li>
            <li><a href="#">Separated link</a></li>
            <li class="divider"></li>
            <li><a href="#">One more separated link</a></li>
          </ul>
        </li>
      </ul>
    </div><!-- /.navbar-collapse -->
  </div><!-- /.container-fluid -->
</nav>