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使用GSON进行JSON内部字段解析

[英]JSON inner field parsing with GSON

I am new to JSON and I love how incredibly potent and straight-forward GSON Api can be, compared to any other parsing methods I've researched. 我是JSON新手,与我研究过的任何其他解析方法相比,我都喜欢GSON Api的强大和直截了当。
I want to parse a rather complex JSON(using GSON) that resembles the following one in terms of structure: 我想解析一个相当复杂的JSON(使用GSON),该JSON在结构上类似于以下内容:

[
  {  
  "name": "Steve",
  "age": 42,
  "description": null,
  "email1": "steve@example.com",
  "email2": null,
  "address1": {
    "type": "home",
    "shippingMethod": "Charge by quantity",
    "street": "Sunrise Ave",
    "streetNo": 17
     },
   "address2": {
    "type": "office",
    "shippingMethod": null,
    "street": "Sunset Ave",
    "streetNo": 71
     },
   "anotherField": "another value"
   },
   {
   "name": "Johnny",
   ...
   "anotherField": "some other value"
   }
]  

I can see that I need to wrap it up with an array of Client objects, because my JSON starts with a "[" and I can also see I need another container class for the inner fields address1 and address2. 我可以看到我需要用一个Client对象数组将其包装起来,因为我的JSON以“ [”开头,而且我还可以看到内部字段address1和address2需要另一个容器类。 This is the container I came up with: 这是我想出的容器:

public class Client {
  String name;
  int age;
  String description;
  String email1;
  String email2;
  ClientAddress address1;
  ClientAddress address2;
  String anotherfield;
  ..
  getters() and setters()

  public class ClientAddress {
    String type;
    String shippingMethod;
    String street;
    int streetNo;
    ..
    getters() and setters()
  }
}

The instruction I wrote to grab the data and populate the wrapper fields is: 我写的获取数据并填充包装器字段的指令是:

Client[] clientsArray= (new Gson()).fromJson(jsonClients, Client[].class);

The result is only partially satisfying; 结果只是部分令人满意; I managed to access all the primitive fields (such as name,email1..), but the address1 and address2 fields are both null. 我设法访问了所有原始字段(例如name,email1 ..),但是address1和address2字段均为null。 As a result, 结果是,

clientsArray[i].getAddress1().getShippingMethod();

returns a null String. 返回一个空字符串。

Where did I go wrong? 我哪里做错了?
Is there a particular way of creating the classes that I am missing? 是否有创建我所缺少的类的特定方法?

Note: My JSON object is perfectly valid from a structure standpoint of view. 注意:从结构的角度来看,我的JSON对象是完全有效的。 If you see any errors, it's probably because they slipped when I was manually creating the above dummy/demo. 如果您看到任何错误,那可能是因为当我手动创建上述虚拟/演示时,它们发生了滑动。

Just to follow GSON Collections good practices , try changing 只是为了遵循GSON Collections的良好做法 ,请尝试更改

 Client[] clientsArray= (new Gson()).fromJson(jsonClients, Client[].class);

to

 Type collectionType = new TypeToken<List<Client>>(){}.getType();
 List<Client> clientsArray = (new Gson()).fromJson(jsonClients, collectionType);

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