JAVA—使用FasterXml.Jackson将XML文件解析为映射

我有以下XML文件：

<?xml version="1.0" encoding="UTF-8"?>
<Site xmlns="bla" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  id="0" affiliations="foo" status="OPERATIONAL" color="#DB2253" updateTime="2002-12-17T09:30:47.0Z" name="GFB_0035" subject="GF">
    <location>
        <vertices Lat="41.905889" Lon="12.452019"/>
        <vertices Lat="41.905973" Lon="12.453596"/>
        <vertices Lat="41.905206" Lon="12.453707"/>
        <vertices Lat="41.905058" Lon="12.452109"/>
    </location>
</Site>

但是，当我查看

“location”

字段的内容时，我只有一个顶点，而不是四个（最后一个）

更新： 我得到的map对象看起来像下面的一个：

{id=0, affiliations=foo, status=OPERATIONAL, color=#DB2253, updateTime=2002-12-17T09:30:47.0Z, name=GFB_0035, subject=GF, location={vertices={Lat=41.905058, Lon=12.452109}}}

是否有一种方法可以使用

FasterXml.Jackson

获取所有四个条目？

根据-

地图不能包含重复的键；每个键最多可以映射到一个值

这就是为什么当你查看“位置”字段的内容时，你只有一个顶点而不是四个（最后一个）

我认为您应该在自己的类中解析XML，而不是将其存储到Map中

参见下面的示例-

import java.io.IOException;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;

public class Stack {


    public static void main(String[] args) throws JsonParseException, JsonMappingException, IOException {

        String xmlFile = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
                + "<Site xmlns=\"bla\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"  id=\"0\" affiliations=\"foo\""
                + " status=\"OPERATIONAL\" color=\"#DB2253\" updateTime=\"2002-12-17T09:30:47.0Z\" name=\"GFB_0035\" "
                + "subject=\"GF\">"
                + "    <location>"
                + "        <vertices lat=\"41.905889\" lon=\"12.452019\"/>"
                + "        <vertices lat=\"41.905973\" lon=\"12.453596\"/>"
                + "        <vertices lat=\"41.905206\" lon=\"12.453707\"/>"
                + "        <vertices lat=\"41.905058\" lon=\"12.452109\"/>"
                + "    </location>"
                + "</Site>";

        XmlMapper mapper = new XmlMapper();
        SiteData site = mapper.readValue(xmlFile, SiteData.class);
        System.out.println(site);
    }

}

LocationData.java

import java.util.List;

import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper;

public class LocationData {

    @JacksonXmlElementWrapper(useWrapping=false)
    private List<VerticesData> vertices;

    public List<VerticesData> getVertices() {
        return vertices;
    }

    public void setVertices(List<VerticesData> vertices) {
        this.vertices = vertices;
    }

    @Override
    public String toString() {
        return "LocationData [vertices=" + vertices + "]";
    }

}

输出：

Site [id=0, affiliations=foo, status=OPERATIONAL, color=#DB2253, updateTime=2002-12-17T09:30:47.0Z, name=GFB_0035, subject=GF, locations=LocationData [vertices=[Vertices [lat=41.905889, lon=12.452019], Vertices [lat=41.905973, lon=12.453596], Vertices [lat=41.905206, lon=12.453707], Vertices [lat=41.905058, lon=12.452109]]]]

---

您的输出是什么样子的？我已经用我的代码的输出更新了这个问题，该位置是否会包含顶点列表？是的，这就是我建议您编写自定义类并将XML解析到该类的原因。@ZachiShtain见更新的答案，我添加了示例。

import java.util.List;

import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper;

public class LocationData {

    @JacksonXmlElementWrapper(useWrapping=false)
    private List<VerticesData> vertices;

    public List<VerticesData> getVertices() {
        return vertices;
    }

    public void setVertices(List<VerticesData> vertices) {
        this.vertices = vertices;
    }

    @Override
    public String toString() {
        return "LocationData [vertices=" + vertices + "]";
    }

}

public class VerticesData {

    private String lat;

    private String lon;

    public String getLat() {
        return lat;
    }

    public void setLat(String lat) {
        this.lat = lat;
    }

    public String getLon() {
        return lon;
    }

    public void setLon(String lon) {
        this.lon = lon;
    }

    @Override
    public String toString() {
        return "Vertices [lat=" + lat + ", lon=" + lon + "]";
    }

}

Site [id=0, affiliations=foo, status=OPERATIONAL, color=#DB2253, updateTime=2002-12-17T09:30:47.0Z, name=GFB_0035, subject=GF, locations=LocationData [vertices=[Vertices [lat=41.905889, lon=12.452019], Vertices [lat=41.905973, lon=12.453596], Vertices [lat=41.905206, lon=12.453707], Vertices [lat=41.905058, lon=12.452109]]]]