Map err = new HashMap();if (!checkLock(session, UserId)) {err.put("err", false);err.put("msg", "该账号已被锁定，请30分钟后重试！");} else {if (用户名及密码匹配) {err.put("err", true);err.put("msg", "登录成功！");// 清空登录失败记录cleanFailNum(session, UserId);} else {// 新增登录失败记录String msg = addFailNum(session, UserId);err.put("err", false);err.put("msg", msg);}}/*** 校验用户登录失败次数* @param session* @param userId* @return*/private boolean checkLock(HttpSession session,String userId) {Object o = session.getServletContext().getAttribute(userId);if(o == null) {return true;}HashMap<String,Object> map = (HashMap<String, Object>) o;int num = Integer.parseInt(Pub.IsNull(map.get("num")));Date date = (Date) map.get("lastDate");long timeDifference = ((new Date().getTime() - date.getTime()) / 60 / 1000);if(num >= 4 && timeDifference < 30) {return false;}return true;}/*** 新增用户登录失败次数* @param session* @param userId*/private String addFailNum(HttpSession session, String userId) {Object o = session.getServletContext().getAttribute(userId);HashMap<String,Object> map = null;int num= 0;if(o == null) {map = new HashMap<String,Object>();}else {map = (HashMap<String, Object>) o;num = Integer.parseInt(Pub.IsNull(map.get("num")));Date date = (Date) map.get("lastDate");long timeDifference = ((new Date().getTime() - date.getTime()) / 60 / 1000);if(timeDifference >= 30) {num = 0;}}map.put("num", num+1);map.put("lastDate", new Date());session.getServletContext().setAttribute(userId, map);String returnStr = "";if (0 != 4-(num+1)) {returnStr = "密码错误，您还有"+(4-(num+1))+"次机会！";} else {returnStr = "该账号已被锁定，请30分钟后重试！";}return returnStr;}/*** 清理用户登录失败的记录* @param session* @param userId*/private void cleanFailNum(HttpSession session, String userId) {session.getServletContext().removeAttribute(userId);}
参考：JAVA密码输入错误3次，锁定账号30分钟简单实现（不操作数据库）_eclipse用户登录三次失败锁死_Man1217的博客-CSDN博客
