反序列化 class 中 json 數組的內容使用 Z6716608096280862A88268CD0DEZ 顯示 null 值

Question

我正在嘗試反序列化具有名稱主題的 json 數組的內容。 反序列化到 pojo 后，主題數組繼續打印 null 即使一切看起來都很好

//入口model

public class MainRequest {

    private  String bookId;
    private List<topics> topics; //called as a list based on the json structure
    
    }

//主題 model

public class topics {
    private String DESCRIPTION;
    private String INDEX;
}

這兩個模型以這種方式在 controller 中執行

@PostMapping(path = "/do-library-request", consumes = "application/json")
    public ResponseEntity<?> process(@RequestBody List<MainRequest> mainRequest,
                                                 HttpServletRequest request
    ) {

        Gson gsons = new Gson();
        
        logger.log(Level.INFO, "Request: {0}", gsons.toJson(mainRequest));
        
        //out from logger
        {"bookId":"155","topics":[{},{}]} // topics are null and this is the problem
                
        .......
    

如何打印主題的價值是挑戰

[{

       "bookId":"155",       

       "topics":[

          {

             "DESCRIPTION":"Little Beginnings",

             "INDEX":"3455"

          },

          {

             "DESCRIPTION":"Nostalgic moments",

             "INDEX":"1234567"

          }

       ],

Answer 1

將 class 主題的變量名稱更改為小寫並添加SerializedName注釋

@Data
public class topics {
    @SerializedName("DESCRIPTION")
    private String description;
    @SerializedName("INDEX")
    private String index;
}

這應該可以解決您的問題。 順便說一句：特別是在這一點上，遵循 java 命名約定很重要