WebDriver Mouse Hover

//The below JavaScript code creates, initializes and dispatches mouse event to an object on fly.
String strJavaScript = "var element = arguments[0];"
            + "var mouseEventObj = document.createEvent('MouseEvents');"
            + "mouseEventObj.initEvent( 'mouseover', true, true );"
            + "element.dispatchEvent(mouseEventObj);";
 
//Then JavascriptExecutor class is used to execute the script to trigger the dispatched event.
((JavascriptExecutor) driver).executeScript(strJavaScript, element);
  

//Getting mouse from driver object
Mouse mouse =((HasInputDevices)driver).getMouse();
 
//Invokes mouseMove method by passing element coordinates as argument
mouse.mouseMove(((Locatable)element).getCoordinates());
  

Actions builder = new Actions(driver);

builder.moveToElement(element).perform();
//Note:  (Preferable for Firefox and HTMLUnit drivers)