如何解析数据以在java中创建对象？

我希望了解如何解析从JSON站点接收的数据。下面是一个数据示例

   { "weatherObservation":{ 
  "clouds": "n/a",
  "weatherCondition": "n/a",
  "observation": "KIAD 181852Z 18005KT 10SM CLR 21/06 A2992 RMK AO2 SLP132 T02110056",
  "windDirection": 180,
  "ICAO": "KIAD",
  "seaLevelPressure": 1013.2,
  "elevation": 93,
  "countryCode": "US",
  "lng": -77.45,
  "temperature": "21.1",
  "dewPoint": "5.6",
  "windSpeed": "05",
  "humidity": 36,
  "stationName": "Washington DC, Washington-Dulles International Airport",
  "datetime": "2011-04-18 18:52:00",
  "lat": 38.93333333333333 }}

我想用所有这些数据制作一个ICAO对象，并用上述内容填充属性

public class ICAO {

    String clouds;
    String weatherCondition;
    String observation;
    int windDirection;
    String ICAOid;
    int seaLevelPressure;
    int elevation;
    String countryCode;
    double lng;
    double temperature;
    double dewpoint;
    int windSpeed;
    int humidity;
    String stationName;
    String date;
    double lat;


public ICAO(String _clouds,String _weatherCondition,String _observation,int _windDirection,String _ICAOid,int _seaLevelPressure,int _elevation, String _countryCode, 
    double _lng, double _temperature, double _dewpoint, int _windSpeed, int _humidity, String _stationName, String _date, double _lat)
{
    clouds = _clouds;
    weatherCondition = _weatherCondition;
    observation = _observation;
    windDirection = _windDirection;
    ICAOid = _ICAOid;
    seaLevelPressure = _seaLevelPressure;
    elevation = _elevation;
    countryCode = _countryCode;
    lng = _lng;
    temperature = _temperature;
    dewpoint = _dewpoint;
    windSpeed = _windSpeed;
    humidity = _humidity;
    stationName = _stationName;
    date = _date;
    lat = _lat;
}

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你可以试着使用from

我在这方面有很好的经验

如果您的ICAO类与JSON数据匹配，那么转换应该像调用

Gson gson = new Gson();
gson.fromJson(JSONstring, ICAO.class);

---

有关详细信息，请阅读。

或者您可以使用。它将为您执行到bean模式类的对象映射。

您可以将JAXB和JSON组合用于此用例：

国际民航组织

import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement(name="weatherObservation")
@XmlAccessorType(XmlAccessType.FIELD)
public class ICAO {

    String clouds;
    String weatherCondition;
    String observation;
    int windDirection;
    @XmlElement(name="ICAO") String ICAOid;
    int seaLevelPressure;
    int elevation;
    String countryCode;
    double lng;
    double temperature;
    double dewpoint;
    int windSpeed;
    int humidity;
    String stationName;
    @XmlElement(name="datetime") String date;
    double lat;

}

演示

import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import javax.xml.stream.XMLStreamReader;

import org.codehaus.jettison.json.JSONObject;
import org.codehaus.jettison.mapped.Configuration;
import org.codehaus.jettison.mapped.MappedNamespaceConvention;
import org.codehaus.jettison.mapped.MappedXMLStreamReader;

public class Demo {

    public static void main(String[] args) throws Exception {
        JAXBContext jc = JAXBContext.newInstance(ICAO.class);

        JSONObject obj = new JSONObject("{\"weatherObservation\":{\"clouds\": \"n/a\",\"weatherCondition\": \"n/a\",\"observation\": \"KIAD 181852Z 18005KT 10SM CLR 21/06 A2992 RMK AO2 SLP132 T02110056\",\"windDirection\": 180,\"ICAO\": \"KIAD\",\"seaLevelPressure\": 1013.2,\"elevation\": 93,\"countryCode\": \"US\",\"lng\": -77.45,\"temperature\": \"21.1\",\"dewPoint\": \"5.6\",\"windSpeed\": \"05\",\"humidity\": 36,\"stationName\": \"Washington DC, Washington-Dulles International Airport\",\"datetime\": \"2011-04-18 18:52:00\",\"lat\": 38.93333333333333 }}");
        Configuration config = new Configuration();
        MappedNamespaceConvention con = new MappedNamespaceConvention(config);
        XMLStreamReader xmlStreamReader = new MappedXMLStreamReader(obj, con);

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        ICAO icao = (ICAO) unmarshaller.unmarshal(xmlStreamReader);

        Marshaller marshaller = jc.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
        marshaller.marshal(icao, System.out);
    }
}

有关更多信息：

---

我很幸运地使用了这里的JSON类：

实际上，您将创建一个JSONObject实例，如下所示：

JSONObject jsonObject = new JSONObject(data);

其中数据是JSON数据的字符串表示形式。从那里，您可以使用以下方法：

获取（字符串）-获取特定的 财产

keys（）-获取 翻译的钥匙

我过去所做的是在自定义对象中创建一个构造函数，该构造函数接收JSON格式的数据，并使用此方法将预期字段解析为实例变量