JSON Jackson ObjectMapper ReadValue - 转换日期时出错

Question

我在尝试将 json 字符串转换为对象时看到下面列出的错误。我没有 Data 类的源代码，它是 jar 文件的一部分。有没有办法可以使用 mixins 来解决这个问题？

代码

ObjectMapper mapper = new ObjectMapper();
mapper.readValue(request, Data.class);

错误

org.codehaus.jackson.map.JsonMappingException: 无法构造 来自 String 值的 javax.xml.datatype.XMLGregorianCalendar 的实例 '10:00:00'：不是有效的表示（错误：无法解析日期 “10:00:00”：不兼容任何标准格式 ("yyyy-MM-dd'T'HH:mm:ss.SSSZ", "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", "EEE, dd MMM yyyy HH:mm:ss zzz", "yyyy-MM-dd"))

JSON 请求

 "timeSlot":{  
       "date":"2015-10-21",
       "endTime":"10:00:00",
       "startTime":"08:00:00",   
 }

编辑

此问题类似于 this ，但是在反序列化时会发生这种情况。另一个解决方案有助于适当地序列化请求。

我已经粘贴了下面不起作用的示例代码 -

import java.io.IOException;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

import javax.xml.datatype.DatatypeConfigurationException;
import javax.xml.datatype.DatatypeConstants;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;

public class TestJSONDeserialize {

    public static void main(String[] args){

        ObjectMapper mapper = new ObjectMapper();
        mapper.addMixIn(Data.class, MyMixin.class);

        String jsonString = "{\"date\":\"2014-02-10\",\"time\":\"16:15:00\"}";
        try {
            mapper.readValue(jsonString, Data.class);
        } catch (JsonParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (JsonMappingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }


}

数据类（我无法更改此文件）

import javax.xml.datatype.XMLGregorianCalendar;

public class Data {

    private XMLGregorianCalendar date;
    private XMLGregorianCalendar time;

    public XMLGregorianCalendar getDate() {
        return date;
    }
    public void setDate(XMLGregorianCalendar date) {
        this.date = date;
    }
    public XMLGregorianCalendar getTime() {
        return time;
    }
    public void setTime(XMLGregorianCalendar time) {
        this.time = time;
    }



}

我在运行时看到以下错误：

com.fasterxml.jackson.databind.exc.InvalidFormatException: 不能 构造 javax.xml.datatype.XMLGregorianCalendar 的实例 字符串值“16:15:00”：不是有效的表示（错误：无法 解析日期值“16:15:00”：无法解析日期“16:15:00”：不是 兼容任何标准形式（“yyyy-MM-dd'T'HH:mm:ss.SSSZ”， "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", "EEE, dd MMM yyyy HH:mm:ss zzz", "yyyy-MM-dd")) 在 [来源：{"date":"2014-02-10","time":"16:15:00"}; 行：1，列：21]（通过参考链： com.comcast.json.test.Data["time"])

Answer 1

已在此旧帖子中回答，但希望这对将来的某人有所帮助。

在ObjectMapper 中指定DateFormat 解决了我的问题。

objectMapper.setDateFormat(new SimpleDateFormat(MY_FORMAT));

Answer 2

我能够使用自定义反序列化器和 mixins 来完成这项工作。下面的代码 -

import java.io.IOException;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

import javax.xml.datatype.DatatypeConfigurationException;
import javax.xml.datatype.DatatypeConstants;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;

public class TestJSONDeserialize {

    public static void main(String[] args){

        ObjectMapper mapper = new ObjectMapper();
        mapper.addMixIn(Data.class, NewMixin.class);

        String jsonString = "{\"date\":\"2014-02-10\",\"time\":\"16:15:00\"}";
        Data data = null;
        try {
            data = mapper.readValue(jsonString, Data.class);
        } catch (JsonParseException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (JsonMappingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        if(data != null){
            System.out.println(" Data " + data.getDate());
            System.out.println(" Data " + data.getTime());
        }   
    }


}



import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.GregorianCalendar;

import javax.xml.datatype.DatatypeConfigurationException;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;

public class CustomDateDeserializer extends JsonDeserializer<XMLGregorianCalendar> {

    private static SimpleDateFormat formatter = 
      new SimpleDateFormat("yyyy-MM-dd");


    @Override
    public XMLGregorianCalendar deserialize(JsonParser jsonparser, DeserializationContext arg1) throws IOException, JsonProcessingException {
        // TODO Auto-generated method stub
        String date = jsonparser.getText();
        try {

            GregorianCalendar c = new GregorianCalendar();
            c.setTime(formatter.parse(date));
            XMLGregorianCalendar date2 = null;
            try {
                date2 = DatatypeFactory.newInstance().newXMLGregorianCalendar(c);
            } catch (DatatypeConfigurationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return date2;
        } catch (ParseException e) {
            throw new RuntimeException(e);
        }
    }
}




import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.GregorianCalendar;

import javax.xml.datatype.DatatypeConfigurationException;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;

public class CustomTimeDeserializer extends JsonDeserializer<XMLGregorianCalendar> {

    private static SimpleDateFormat formatter = 
      new SimpleDateFormat("hh:mm:ss");


    @Override
    public XMLGregorianCalendar deserialize(JsonParser jsonparser, DeserializationContext arg1) throws IOException, JsonProcessingException {
        // TODO Auto-generated method stub
        String date = jsonparser.getText();
        try {

            GregorianCalendar c = new GregorianCalendar();
            c.setTime(formatter.parse(date));
            XMLGregorianCalendar date2 = null;
            try {
                date2 = DatatypeFactory.newInstance().newXMLGregorianCalendar(c);
            } catch (DatatypeConfigurationException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return date2;
        } catch (ParseException e) {
            throw new RuntimeException(e);
        }
    }
}



import javax.xml.datatype.XMLGregorianCalendar;

import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;

abstract class NewMixin {

    @JsonDeserialize(using = CustomDateDeserializer.class)
    public abstract void setDate(XMLGregorianCalendar date);

    @JsonDeserialize(using = CustomTimeDeserializer.class)
    public abstract void setTime(XMLGregorianCalendar time);
}

Answer 3

见here。在您的字段上粘贴日期格式化程序：

@JsonFormat(shape=JsonFormat.Shape.STRING, pattern="HH:mm:ss", timezone="CET")
private Date startTime;