java 将 JSON 响应转换为 List<T>
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Convert JSON response into List<T>
提问by user3478224
I am new to GSON. I need to convert the following JSON response into a List.
我是 GSON 的新手。我需要将以下 JSON 响应转换为列表。
JSON response:
JSON 响应：
{
"data": [{
"data": {
"ac_id": "000",
"user_id": "000",
"title": "AAA"
}
}, {
"data": {
"ac_id": "000",
"user_id": "000",
"title": "AAA"
}
}]
}
I have a class to cast data
我有一个类来投射数据
Account. java
帐户。爪哇
public class Account {
public int ac_id;
public int user_id;
public String title;
@Override
public String toString(){
return "Account{"+
"ac_id="+ac_id+
", user_id="+user_id+
", title="+title+'}';
}
}
When I cast the response with my class I get:
当我和我的班级一起回答时，我得到：
[Account{ac_id="000", user_id="000", title="AAA"}, Account{ac_id="000", user_id="000", title="AAA"}]
Now I need to put these two values into a List<Account>.
What do you suggest?
现在我需要将这两个值放入一个List<Account>.
你有什么建议？
回答by Elias N
JSONObject data = new JSONObject(response);
JSONArray accounts = data.getJSONArray("data");
List<Account> accountList = new Gson().fromJson(accounts.toString(), new TypeToken<ArrayList<Account>>(){}.getType());
If you cannot change your JSON response to remove the inner "data" key, you can use this:
如果您无法更改 JSON 响应以删除内部“数据”键，则可以使用：
Gson gson = new Gson();
ArrayList<Account> accountList = new ArrayList<Account>();
JSONArray accounts = data.getJSONArray("data");
for (int i = 0; i < accounts.length(); i++) {
JSONObject a = accounts.getJSONObject(i).getJSONObject("data");
accountList.add(gson.fromJson(a.toString(), Account.class));
}
回答by MezzDroid
For that you can use Tokens so that gson can understand the custom type...
为此，您可以使用令牌，以便 gson 可以理解自定义类型...
TypeToken<List<Account>> token = new TypeToken<List<Account>>(){};
List<Account > accountList= gson.fromJson(response, token.getType());
for(Account account : accountList) {
//some code here for looping }
回答by OneCricketeer
That nested "data"key is pointless. If you can fix your JSON you should make this instead.
那个嵌套的"data"键是没有意义的。如果您可以修复您的 JSON，您应该改为使用它。
{
"data": [{
"ac_id": "000",
"user_id": "000",
"title": "AAA"
}, {
"ac_id": "000",
"user_id": "000",
"title": "AAA"
}]
}
And then this will work.
然后这将起作用。
JSONObject data = new JSONObject(response);
JSONArray accounts = data.getJSONArray("data");
List<Account> accountList = new Gson()
.fromJson(accounts.toString(), new TypeToken<ArrayList<Account>>(){}.getType());
Or, again, that first "data"isn't really necessary either.
If you can get your JSON just to be the list of Accounts...
或者，同样，这"data"也不是真正必要的。
如果你可以让你的 JSON 只是作为帐户列表......
[{
"ac_id": "000",
"user_id": "000",
"title": "AAA"
}, {
"ac_id": "000",
"user_id": "000",
"title": "AAA"
}]
This will work
这将工作
List<Account> accountList = new Gson()
.fromJson(response, new TypeToken<ArrayList<Account>>(){}.getType());
回答by koceeng
if you have access to where the JSON was created, i think you should make it like this:
如果您可以访问创建 JSON 的位置，我认为您应该这样做：
{"data":[{"ac_id":"000","user_id":"000","title":"AAA"},{"ac_id":"000","user_id":"000","title":"AAA"}]}
then to convert it, just use this code: (where jsonString is the string above)
然后转换它，只需使用此代码：（其中 jsonString 是上面的字符串）
List<Account> accountList = new Gson().fromJson(jsonString, new TypeToken<ArrayList<Account>>(){}.getType());
