我正在尝试使用 MOXy 解码具有以下结构的 json:
[
{
"page": 1,
"pages": 1
},
[
{
"indicator": {
"id": "IC.BUS.EASE.XQ",
"value": "Ease of doing business index"
},
"country": {
"id": "1A",
"value": "Arab World"
},
"value": "113.952380952381",
"date": "2014"
},
...
]
]
数组的第一个元素是一个对象,第二个元素是另一个复杂元素的数组。我真的在 SO 和 MOXy 文档中搜索了一个类似的例子,但没有成功。
我将 json 文档映射到 JAVA 类的最佳尝试如下。根类是 CountryDataResponse(省略了 getter 和 setter):
@XmlRootElement
@XmlType(propOrder ={"paginationInfo", "dataArray"})
public class CountryDataResponse {
private DataArray dataArray;
private PaginationInfo paginationInfo;
}
(我知道这会失败,因为它不是数组,但我完全迷失了。)
PaginationInfo 类模拟根数组的第一个元素,DataArray 类包装第二个元素,这是一个数据类元素数组。此外,我还为每个数据元素内的复杂类型创建了 Indicator 和 Country 类。
主要类(省略指标和国家/地区):
@XmlRootElement(name = "paginationInfo")
@XmlAccessorType(XmlAccessType.FIELD)
public class PaginationInfo {
private int page;
private int pages;
}
@XmlRootElement( name = "dataArray" )
public class DataArray {
List<Data> datas;
}
@XmlRootElement(name="data")
@XmlAccessorType(XmlAccessType.FIELD)
public class Data {
private Indicator indicator;
private Country country;
private String date;
private double value;
}
现在,调试以下代码:
public static void main(String args[]) {
String test = "[{\"page\": 1,\"pages\": 1,\"per_page\": \"1000\",\"total\": 248},"
+ "["
+ "{\"indicator\": {\"id\": \"NY.GDP.MKTP.CD\",\"value\": \"GDP (current US$)\"},"
+ "\"country\": {\"id\": \"1A\",\"value\": \"Arab World\"},"
+ "\"value\": \"2853079422103.94\","
+ "\"decimal\": \"1\","
+ "\"date\": \"2013\"},"
+ "{\"indicator\": {\"id\": \"NY.GDP.MKTP.CD\",\"value\": \"GDP (current US$)\"},"
+ "\"country\": {\"id\": \"S3\",\"value\": \"Caribbean small states\"},"
+ "\"value\": \"67033118185.1864\","
+ "\"decimal\": \"1\","
+ "\"date\": \"2013\"}"
+ "]]";
JAXBContext jc = JAXBContext.newInstance(CountryDataResponse.class, Country.class, Data.class, DataArray.class, Indicator.class, PaginationInfo.class);
Unmarshaller unmarshaller = jc.createUnmarshaller();
unmarshaller.setProperty(UnmarshallerProperties.MEDIA_TYPE, MediaType.APPLICATION_JSON);
unmarshaller.setProperty(UnmarshallerProperties.JSON_INCLUDE_ROOT, false);
Object res = unmarshaller.unmarshal(json, CountryDataResponse.class);
}
res 对象(属于 JAXBElement 类)有一个ArrayList 类型的值。数组的第一个元素是类CountryDataResponse的对象(它应该是PaginationInfo),第二个 是另一个ArrayList,其元素也属于 CountryDataResponse 类(它们应该 是数据实例)。
谁能帮帮我,或者它只是一个格式错误的 json,无法正确地自动解码?
提前谢谢你。
最佳答案
虽然 JSON 是有效的,但我建议更改结构,大致如下:
{
"paginationInfo": {
"page": 1,
"pages": 1
},
"dataArray": [
{
"indicator": {
"id": "IC.BUS.EASE.XQ",
"value": "Ease of doing business index"
},
"country": {
"id": "1A",
"value": "Arab World"
},
"value": "113.952380952381",
"date": "2014"
}
]
这将允许您使用“键”名称提取您想要的数据,这正是 JSON 的用途。
另一种方法是将数据数组嵌入分页对象中:
{
"page": 1,
"pages": 1,
"dataArray": [
{
"indicator": {
"id": "IC.BUS.EASE.XQ",
"value": "Ease of doing business index"
},
"country": {
"id": "1A",
"value": "Arab World"
},
"value": "113.952380952381",
"date": "2014"
}
]
这种方法将允许您创建一个通用的页面包装器,如果您有多种格式要分页,这可能会很有用。
希望这对您有所帮助。
关于java - JAXB:解码异构数组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30165543/