Json字符串到Java对象Gson

Question

我有一个这种格式的json字符串：

 [
   {
     "key1": { "key1":"val1","key2":"val2" },
     "key2": { "key1":"val1","key2":"val2" }
   }
]   

要解析它，我创建了一个java类：

class data {
     String key;
     List <content> listdata;
     /* getter and setter for the attribute above */
     ...
   } 

现在我关注了Gson文档，并尝试提取数据：

Gson gson =new Gson();
data[] ints = gson.fromJson(MyjsonString, data[].class); 

我从Gson API得到解析错误，我做错了什么？

java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1 path

Answer 1

用于解析json，如下面的课程

class data {
String key;
List <content> listdata;
/* getter and setter for the attribute above */
...
} 

您需要json，如下所示

"data" : {
 "key": "value",
 "listdata": [{ content object key attributes here }]
}

正如你的例外清楚地说BEGIN_ARRAY but was STRING所以你必须在json中使用数组进行解析。

回复您的评论

如果你想要一个解析json

的类

{
 "key1": { "key1":"val1","key2":"val2" },
 "key2": { "key1":"val1","key2":"val2" }
}

然后你将有如下的类结构

class Data {
 Map<String, String> key1;
 Map<String, String> key2;
 /* getter and setter for the attribute above */
} 

Answer 2

根据Json，这个类结构有效：

class data {
 List <Map<String,Content> data;
 /* getter and setter for the attribute above */
 ...

}