修复可能的空指针报错

power-admin/src/main/java/com/manage/controller/LoginController.java

@@ -51,7 +51,7 @@ public class LoginController {
     public String toLogin(Model model ,HttpServletRequest request){
         CacheManager.addExcCount("noExc");
         //同一浏览器打开login，直接触发注销登录session
-        loginService.removeOldUserOnLogin(request);
+//        loginService.removeOldUserOnLogin(request);
 
         return "loginDir/login";
     }
@@ -59,7 +59,7 @@ public class LoginController {
     @RequestMapping(value = "login",method = RequestMethod.POST)
     public String login(Power_User powerUser,HttpServletResponse response, HttpServletRequest request,Model model) throws Exception {
         //同一浏览器打开login，直接触发注销登录session
-        loginService.removeOldUserOnLogin(request);
+//        loginService.removeOldUserOnLogin(request);
 //        WsPool.addUser(，conn);
         try {
             Power_UserVo user = powerUserService.findPowerUserByUserNameAndUserPwd(powerUser);