????public?ModelAndView?handleRequest(HttpServletRequest?request,?HttpServletResponse?response)?throws?Exception{??

????????//?Set?to?expire?far?in?the?past.??

????????response.setDateHeader("Expires",?0);??

????????//?Set?standard?HTTP/1.1?no-cache?headers.??

????????response.setHeader("Cache-Control",?"no-store,?no-cache,?must-revalidate");??

????????//?Set?IE?extended?HTTP/1.1?no-cache?headers?(use?addHeader).??

????????response.addHeader("Cache-Control",?"post-check=0,?pre-check=0");??

????????//?Set?standard?HTTP/1.0?no-cache?header.??

????????response.setHeader("Pragma",?"no-cache");??

??

????????//?return?a?jpeg??

????????response.setContentType("image/jpeg");??

??

????????//?create?the?text?for?the?image??

????????String?capText?=?captchaProducer.createText();??

??

????????//?store?the?text?in?the?session??

????????request.getSession().setAttribute(Constants.KAPTCHA_SESSION_KEY,?capText);??

??

????????//?create?the?image?with?the?text??

????????BufferedImage?bi?=?captchaProducer.createImage(capText);??

??

????????ServletOutputStream?out?=?response.getOutputStream();??

??

????????//?write?the?data?out??

????????ImageIO.write(bi,?"jpg",?out);??

????????try?{??

????????????out.flush();??

????????}?finally?{??

????????????out.close();??

????????}??

????????return?null;??

????}??

}??

?

3.校驗用戶輸入的Controller

?

?

Java代碼??

?

/**?

?*?ClassName:?LoginController?
?

?*?Function:?登錄Controller.?
?

?*?date:?2013-12-10?上午11:41:43?
?

?*?

?*?@author?chenzhou1025@126.com?

?*/??

@Controller??

@RequestMapping("/login")??

public?class?LoginController?{??

??

????/**?

?????*?loginCheck:ajax異步校驗登錄請求.?
?

?????*?

?????*?@author?chenzhou1025@126.com?

?????*?@param?request?

?????*?@param?username?用戶名?

?????*?@param?password?密碼?

?????*?@param?kaptchaReceived?驗證碼?

?????*?@return?校驗結果?

?????*?@since?2013-12-10?

?????*/??

????@RequestMapping(value?=?"check",?method?=?RequestMethod.POST)??

????@ResponseBody??

????public?String?loginCheck(HttpServletRequest?request,??