java - 我的 AJAX 不会运行 SUCCESS 函数，但会执行我的 Controller JAVA

Question

我正在尝试执行我的 Controller 并获取用于我的警报消息的返回字符串，但我的成功函数不起作用。它执行 Controller 但不执行成功函数。错误执行但不显示任何消息。 下面是 AJAX

var jsonData = {
				"appIDHidden": appname,
				"txtypeHidden": txtype,
				"ipaddress": ipaddress
			};
			$.ajax({
			  type: 'POST',
			  url: "checkaccesspermission",
			  data: jsonData,
			  dataType: 'json',
			  success: function(data) {
					if(data != "exists"){
						alert('Permission Already Exists!');
						return false;
					}else{
						alert('Add Permission test Succesful!');
						return true;	
					}
					alert('test123');
				},
				error: function(jqXHR, textStatus, thrownError)
				{
					alert(thrownError+jsonData[1]);
				},
			  async: false
			});

下面是 Controller

 @RequestMapping(value="/checkaccesspermission", method=RequestMethod.POST)
    public String checkaccesspermission(@ModelAttribute("loginForm") IpAccessManagementModel loginForm, Model model,
            HttpSession session, BindingResult result,HttpServletRequest request,
            @RequestParam("ipaddress") String ipaddress,
            @RequestParam("txtypeHidden") String txtype,
            @RequestParam("appIDHidden") String appID) throws IOException{
            System.out.println("CHECKACCESSPERMISSIONs");
            IpAccessManagementModel sub = new IpAccessManagementModel();
            sub.setAppName(appID);
            sub.setTxtType(txtype);
            sub.setIpAddress(ipaddress);
            System.out.println(ipaddress);
            ipAccessMGTDAO.addPermission(sub);
            String resultCheckExist = ipAccessMGTDAO.checkAccessPermission(sub);
            System.out.println("checkResult:|"+resultCheckExist+"|");
            return resultCheckExist;
    }

Answer 1

没关系，我通过在 Controller 上添加 @public ResponseBody 来让它工作:@RequestMapping(value="/checkaccesspermission", method=RequestMethod.POST) 公共(public)@ResponseBody 字符串检查访问权限