GSON：用随机类名称反序列化Json [英] GSON: Deserializing Json with random class names

问题描述

我正在尝试使用GSON将一些Json反序列化为一个漂亮整洁的对象。现在，我设法让Json正确映射一些更明显的变量。然而，在试图映射某些Json时，我遇到了这个问题：

  {
this_number：1， 
that_number：12，
some_string：String！，
list_of_objects：{
342356676784653234535345：{
random_double： 0.1235667456456，
magic：29，
health：1，
price：7，
point：{
x ：2，
y：70 
} 
}，
2345263767467354：{
random_double：0.1235667456456，
魔术：23，
健康：1，
价格：9，
点数：{
x：0，
 y：70 
} 
} 
} 
} 
  

它很好地映射，直到我来到list_of_objects。我不能为我的生活制定出如何实施它。我认为主要问题是它们不再是静态类名，它们是随机的。因此，写下如下内容是完全不切实际的（也是不可能的）：

  class 342356676784653234535345 {
 double random_double = 0.0 ; 
 // etc 
} 
  

我查看了一下Stackoverflow，但答案似乎相当复杂，许多人并没有完全回答我想知道的内容。

我玩过简单的Object方法，使用这里，但我找不到任何关于它的用法的更多信息。

我也继续找到映射到泛型的引用，但我不太明白发生了什么。 例如

JsonDeserializer

假设您有映射类

  public class Data {
 private int this_number; 
 private int that_number; 
 private String some_string; 
私人清单< DataInfo>对象; 
} 
 
公共类DataInfo {
 private double random_double; 
 private int magic; 
 private int health; 
私有诠释价格; 
} 
 
 public class Point {
 int x; 
 int y; 
 
  

CustomDeserializer

  public class CustomDeserializer实现了JsonDeserializer< Data> {
 
 @Override 
 public Data deserialize（final JsonElement json，final Type typeOfT，final JsonDeserializationContext context）throws JsonParseException {
 final JsonObject jsonObject = json.getAsJsonObject（）; 
 
 final int this_number = jsonObject.get（this_number）。getAsInt（）; 
 final int that_number = jsonObject.get（that_number）。getAsInt（）; 
 final String some_string = jsonObject.get（some_string）。getAsString（）; 
 
 JsonObject list_of_objects = jsonObject.get（list_of_objects）。getAsJsonObject（）; 
 
设置< Entry< String，JsonElement>> objects = list_of_objects.entrySet（）; 
 
 final Data data = new Data（）; 
清单< DataInfo> list = new ArrayList<>（）; 
 
 Gson gson = new Gson（）; （Entry< String，JsonElement> entry：objects）
 
 {
 JsonElement jsonElement = entry.getValue（）; 
 DataInfo info = gson.fromJson（jsonElement，DataInfo.class）; 
 list.add（info）; 
} 
 
 data.setObjects（list）; 
 data.setSome_string（some_string）; 
 data.setThat_number（that_number）; 
 data.setThis_number（this_number）; 
 
返回数据; 
} 
} 
  

I'm trying to use GSON to deserialize some Json to a nice, tidy object. Now, I have managed to get the Json to correctly map to some of the more obvious variables. However, while trying to map some of the Json I came across this:

{
    "this_number": 1,
    "that_number": 12,
    "some_string": "String!",
    "list_of_objects": {
        "342356676784653234535345": {
            "random_double": "0.1235667456456",
            "magic": "29",
            "health": 1,
            "price": 7,
            "point": {
                "x": 2,
                "y": 70
            }
        },
        "2345263767467354": {
            "random_double": "0.1235667456456",
            "magic": "23",
            "health": 1,
            "price": 9,
            "point": {
                "x": 0,
                "y": 70
            }
        }
    }
}

It was mapping nicely until I came to "list_of_objects". I can't for the life of me work out how to implement it. I think the main issue is that they are no longer static class names, they are randomized. Therefore it would be totally impractical (and impossible) to write something like:

class 342356676784653234535345{
    double random_double = 0.0;
    //etc
}

I've had a look around Stackoverflow, but the answers seem quite complex and many don't quite answer what I'm wanting to know.

I have played around with the plain Object method used here, but I couldn't find any further information on its usage.

I also keep finding references to mapping to generic types, but I don't quite understand what is going on. For example

解决方案

You can convert a JSON string to an equivalent Java object using custom Gson JsonDeserializer

Assuming you have mapping classes

public class Data {
    private int this_number;
    private int that_number;
    private String some_string;
    private List<DataInfo> objects;
}

public class DataInfo {
    private double random_double;
    private int magic;
    private int health;
    private int price;
}

public class Point {
    int x ;
    int y;
}

CustomDeserializer

public class CustomDeserializer implements JsonDeserializer<Data> {

    @Override
    public Data deserialize(final JsonElement json, final Type typeOfT, final JsonDeserializationContext context) throws JsonParseException {
        final JsonObject jsonObject = json.getAsJsonObject();

        final int this_number = jsonObject.get("this_number").getAsInt();
        final int that_number = jsonObject.get("that_number").getAsInt();
        final String some_string = jsonObject.get("some_string").getAsString();

        JsonObject list_of_objects =jsonObject.get("list_of_objects").getAsJsonObject();

        Set<Entry<String, JsonElement>> objects =  list_of_objects.entrySet();

        final Data data = new Data();
        List<DataInfo> list = new ArrayList<>();

        Gson gson = new Gson();

        for (Entry<String, JsonElement> entry : objects) {
            JsonElement jsonElement  = entry.getValue();
            DataInfo info = gson.fromJson(jsonElement,DataInfo.class);
            list.add(info);
        }

        data.setObjects(list);
        data.setSome_string(some_string);
        data.setThat_number(that_number);
        data.setThis_number(this_number);

        return data;
    }
}

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