[排錯] SpringBoot 警告 Could not find acceptable representation

環境

Java 1.8

SpringBoot 2.1.9

Java 接口代碼

    @ResponseBody
    @RequestMapping(value = "cloud", method = RequestMethod.GET,produces = "applications/json;charset=UTF-8")
    public Boolean queryItemInfoAllInCloud(){
        ItemInfo itemInfo = itemService.queryItemInfoAllInCloud();
        if(itemInfo == null) return false;
        return true;
    }

請求路徑

http://127.0.0.1:8080/controller/cloud/

警告信息

2019-11-14 14:56:57.465  WARN 57604 Resolved [org.springframework.web.HttpMediaTypeNotAcceptableException: Could not find acceptable representation]

這句話翻譯過來就是 "找不到可接受的表示" 可以理解為瀏覽器找不到合適的類型來顯示請求接口的返回值?

然后問題是出在 

produces = "applications/json;charset=UTF-8"

這段代碼的意思是返回 json 類型的響應數據, 但是我們接口的返回值是 Boolean 類型的, 當然無法返回

所以要這段代碼改成

produces=MediaType.APPLICATION_JSON_VALUE

問題圓滿解決