使用GSON问题解析JSON

Question

解析JSON中嵌套的键值对时出现的问题。

JSON结构

 {  
   "data":{  
      "action":"item1",
      "react":"item2",
        "categories":{  
         "Price":{  
            "$0-$10":{  
               "Refine":"false",
               "bcc":"2"               
            },
            "$251-$500":{  
               "Refine":"false",
               "bcc":"2"
            }
         },
         "Gender":{  
            "Girl":{  
              "Refine":"false",
               "bcc":"2"
            },
            "Boy":{  
            "Refine":"false",
               "bcc":"2"
            }
         }
    }
}}

将以下类定义为POJO

class Product
{
public Data data;

public class Data{

   public String action;

   public String react;

   public Map<String,Map<String,request>> categories;

}}

public class request{
  public string Refine;
  public String bcc
}

JSON元素“类别”中的键值对是动态的。

Product responseData = gson.fromJson(jsoninput,
                Product.class);

尝试使用gson和pogo类产品解析上述JSON

1. 字段动作，反应被解析为正确。
2. 字段类别返回空Map。

Answer 1

我使用的是GSON版本2.3，从maven下载它。只需创建一个项目，复制其中的所有内容，并设置json文件路径并按RUN：

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;


public class main {
    public static void main(String[] args) {


        Gson gson = new Gson();


        try {

            BufferedReader br = new BufferedReader(
                    new FileReader("your json file path"));

            // Deserialization
            Product obj = gson.fromJson(br, Product.class);


            // Serialization
            gson = new GsonBuilder().setPrettyPrinting().create();
            String json = gson.toJson(obj);
            System.out.println(json);


        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

您的POJO课程：

import java.util.Map;


class Product
{
    public Data data;

    public class Data{

        public String action;

        public String react;

        public class request{
            public String Refine;
            public String bcc;
        }

        public Map<String,Map<String,request>> categories;

    }
}

最后是你的json字符串：

   {
       "data":{  
         "action":"item1",
         "react":"item2",
         "categories":{  
            "Price":{  
               "$0-$10":{  
                  "Refine":"false",
                  "bcc":"2"               
               },
               "$251-$500":{  
                  "Refine":"false",
                  "bcc":"2"
               }
            },
            "Gender":{  
               "Girl":{  
                 "Refine":"false",
                  "bcc":"2"
               },
               "Boy":{  
               "Refine":"false",
                  "bcc":"2"
               }
            }
        }

       }
     }