嵌套数组的GSON解析

Question

我很难理解 GSON 是否可以默认处理这种 json 或者我是否需要为每个子元素实现反序列化器。

json 输入

{
   "services":[
      {
         "id": 2,
         "name": "Buy"
      },
      {
         "id": 3,
         "name": "Sell"
      }
      ]
   "status": {
      "code": 0,
      "message": ""
   }
}

对我而言，最好的结果是让以下 class 包含所有数据

java [POJO]

public class Services {
    public List<ServiceItem> services;
    public Status status;

    public class ServiceItem {
        public int id;
        public String name;
    }

    public class Status {
        public int code;
        public String message;
    }
}

是否可以让 GSON class 和 json 让它工作？或者我是否需要为每个子 class 创建反序列化器？

Answer 1

按如下更正您的 json 输入（您忘记了 status 字段前的逗号）

{
   "services":[
      {
         "id": 2,
         "name": "Buy"
      },
      {
         "id": 3,
         "name": "Sell"
      }
      ],
   "status": {
      "code": 0,
      "message": ""
   }
}

那么让我们考虑一下你的类如下

public class Services {
    public List<ServiceItem> services;
    public Status status;
    // getters and setters
    @Override
    public String toString() {
        return "["+services.toString()+status.toString()+"]";
    }

    public class ServiceItem {
        public int id;
        public String name;
        // getters and setters
        @Override
        public String toString() {
            return "("+id+","+name+")";
        }

    }

    public class Status {
        public int code;
        public String message;
        // getters and setters
        @Override
        public String toString() {
            return ",("+code+","+message+")";
        }
    }
}

如果输入是一个文件jsonInput.json那么

Gson gson = new Gson();
Services data = gson.fromJson(new BufferedReader(new FileReader(
        "jsonInput.json")), new TypeToken<Services>() {
}.getType());
System.out.println(data);

如果输入是 json 字符串 jsonInput 那么

Gson gson = new Gson();
Services data = gson.fromJson(jsonInput, Services.class);
System.out.println(data);

输出：

[[(2,Buy), (3,Sell)],(0,)]

嵌套数组的GSON解析

GSON parsing of nested array

java

json

gson