JAXB:如何将map映射到值。-JAXB:howtomarshallmapintovalue

6  

I didn't see anything that really answered this very well. I found something that worked pretty well here:

我没有看到任何能很好地回答这个问题的东西。我发现了一些非常有用的东西:

Use JAXB XMLAnyElement type of style to return dynamic element names

使用JAXB XMLAnyElement样式类型返回动态元素名称

I modified it a bit to support hashmap trees. You could add other collections.

我对它做了一点修改，以支持hashmap树。您可以添加其他集合。

public class MapAdapter extends XmlAdapter> {
    @Override
    public MapWrapper marshal(Map m) throws Exception {
        MapWrapper wrapper = new MapWrapper();
        List elements = new ArrayList();
        for (Map.Entry property : m.entrySet()) {

            if (property.getValue() instanceof Map)
                elements.add(new JAXBElement(new QName(getCleanLabel(property.getKey())),
                        MapWrapper.class, marshal((Map) property.getValue())));
            else
                elements.add(new JAXBElement(new QName(getCleanLabel(property.getKey())),
                        String.class, property.getValue().toString()));
        }
        wrapper.elements = elements;
        return wrapper;
    }

    @Override
    public Map unmarshal(MapWrapper v) throws Exception {
        // TODO
        throw new OperationNotSupportedException();
    }

    // Return a XML-safe attribute.  Might want to add camel case support
    private String getCleanLabel(String attributeLabel) {
        attributeLabel = attributeLabel.replaceAll("[()]", "").replaceAll("[^\\w\\s]", "_").replaceAll(" ", "_");
        return attributeLabel;
    }
}
class MapWrapper {
    @XmlAnyElement
    List elements;
}

Then to implement it:

然后去实现它:

static class myxml {
    String name = "Full Name";
    String address = "1234 Main St";
    // I assign values to the map elsewhere, but it's just a simple
    // hashmap with a hashmap child as an example.
    @XmlJavaTypeAdapter(MapAdapter.class)
    public Map childMap;
}

Feeding this through a simple Marshaller gives output that looks like this:

通过一个简单的编组器进行输入，输出如下所示:

    Full Name
    
1234 Main St
    
        value2
        value1
        
            childvalue1
        
    

3  

(Sorry, can't add comments)

(对不起,不能添加评论)

In Blaise's answer above, if you change:

在以上布莱斯的回答中，如果你改变:

@XmlJavaTypeAdapter(MapAdapter.class)
public Map getMapProperty() {
    return mapProperty;
}

to:

:

@XmlJavaTypeAdapter(MapAdapter.class)
@XmlPath(".") // <<-- add this
public Map getMapProperty() {
    return mapProperty;
}

then this should get rid of the tag, and so give you:

那么这个应该可以去掉 标签，所以给你:

ALTERNATIVELY:

另外:

You can also change it to:

您也可以将其更改为:

@XmlJavaTypeAdapter(MapAdapter.class)
@XmlAnyElement // <<-- add this
public Map getMapProperty() {
    return mapProperty;
}

and then you can get rid of AdaptedMap altogether, and just change MapAdapter to marshall to a Document object directly. I've only tested this with marshalling, so there may be unmarshalling issues.

然后您可以完全摆脱AdaptedMap，直接将MapAdapter更改为marshall文档对象。我只对它进行了编组测试，因此可能存在编组问题。

I'll try and find the time to knock up a full example of this, and edit this post accordingly.

我将尝试找出时间来编写一个完整的示例，并相应地编辑这篇文章。

2  

I have solution without adapter. Transient map converted to xml-elements and vise versa:

我有没有适配器的解决方案。瞬态映射转换为xml元素，反之亦然:

@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement(name = "SchemaBasedProperties")
public class SchemaBasedProperties
{
  @XmlTransient
  Map> properties;

  @XmlAnyElement(lax = true)
  List xmlmap;

  public Map> getProperties()
  {
    if (properties == null)
      properties = new LinkedHashMap>(); // I want same order

    return properties;
  }

  boolean beforeMarshal(Marshaller m)
  {
    try
    {
      if (properties != null && !properties.isEmpty())
      {
        if (xmlmap == null)
          xmlmap = new ArrayList();
        else
          xmlmap.clear();

        javax.xml.parsers.DocumentBuilderFactory dbf = javax.xml.parsers.DocumentBuilderFactory.newInstance();
        javax.xml.parsers.DocumentBuilder db = dbf.newDocumentBuilder();
        org.w3c.dom.Document doc = db.newDocument();
        org.w3c.dom.Element element;

        Map attrs;

        for (Map.Entry> it: properties.entrySet())
        {
          element = doc.createElement(it.getKey());
          attrs = it.getValue();

          if (attrs != null)
            for (Map.Entry at: attrs.entrySet())
              element.setAttribute(at.getKey(), at.getValue());

          xmlmap.add(element);
        }
      }
      else
        xmlmap = null;
    }
    catch (Exception e)
    {
      e.printStackTrace();
      return false;
    }

    return true;
  }

  void afterUnmarshal(Unmarshaller u, Object p)
  {
    org.w3c.dom.Node node;
    org.w3c.dom.NamedNodeMap nodeMap;

    String name;
    Map attrs;

    getProperties().clear();

    if (xmlmap != null)
      for (Object xmlNode: xmlmap)
        if (xmlNode instanceof org.w3c.dom.Node)
        {
          node = (org.w3c.dom.Node) xmlNode;
          nodeMap = node.getAttributes();

          name = node.getLocalName();
          attrs = new HashMap();

          for (int i = 0, l = nodeMap.getLength(); i  attrs;

    attrs = new HashMap();
    attrs.put("ResId", "A_LABEL");
    props.getProperties().put("LABEL", attrs);

    attrs = new HashMap();
    attrs.put("ResId", "A_TOOLTIP");
    props.getProperties().put("TOOLTIP", attrs);

    attrs = new HashMap();
    attrs.put("Value", "hide");
    props.getProperties().put("DISPLAYHINT", attrs);

    javax.xml.bind.JAXBContext jc = javax.xml.bind.JAXBContext.newInstance(SchemaBasedProperties.class);

    Marshaller marshaller = jc.createMarshaller();
    marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
    marshaller.marshal(props, new java.io.File("test.xml"));

    Unmarshaller unmarshaller = jc.createUnmarshaller();
    props = (SchemaBasedProperties) unmarshaller.unmarshal(new java.io.File("test.xml"));

    System.out.println(props.getProperties());
  }
}

My output as espected:

我的输出,除了:

    
    
    


{LABEL={ResId=A_LABEL}, TOOLTIP={ResId=A_TOOLTIP}, DISPLAYHINT={Value=hide}}

You can use element name/value pair. I need attributes... Have fun!

可以使用元素名称/值对。我需要属性……玩得开心!

2  

Seems like this question is kind of duplicate with another one, where I've collect some marshal/unmarshal solutions into one post. You may check it here: Dynamic tag names with JAXB.

看起来这个问题和另一个问题有点相似，我在一个帖子中收集了一些封送/封送解决方案。您可以在这里检查它:使用JAXB的动态标记名称。

In short:

简而言之:

1. A container class for @xmlAnyElement should be created
2. 应该为@xmlAnyElement创建一个容器类
3. An XmlAdapter can be used in pair with @XmlJavaTypeAdapter to convert between the container class and Map<>;
4. XmlAdapter可以与@XmlJavaTypeAdapter一起使用，在容器类和映射<>之间进行转换;

0  

I found easiest solution.

我发现最简单的解决方案。

@XmlElement(name="attribute")
    public String[] getAttributes(){
        return attributes.keySet().toArray(new String[1]);
    }
}

Now it will generate in you xml output like this:

现在，它将在您的xml输出中生成如下内容:

key1
...
keyN

0  

When using xml-apis-1.0, you can serialize and deserialize this:

在使用xml-api -1.0时，您可以对其进行序列化和反序列化:

Using this code:

使用这段代码:

import java.io.File;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlAnyElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;

@XmlRootElement
class Root {

    public XmlRawData map;

}

public class Demo {

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

        Unmarshaller unmarshaller = jc.createUnmarshaller();
        Root root = (Root) unmarshaller.unmarshal(new File("src/input.xml"));

        System.out.println(root.map.getAsMap());

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

class XmlRawData {

    @XmlAnyElement
    public List elements;

    public void setFromMap(Map values) {

        Document document;
        try {
            document = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument();
        } catch (ParserConfigurationException e) {
            throw new RuntimeException(e);
        }

        for (Entry entry : values.entrySet()) {
            Element mapElement = document.createElement(entry.getKey());
            mapElement.appendChild(document.createTextNode(entry.getValue()));
            elements.add(mapElement);
        }
    }

    public Map getAsMap() {
        Map map = new HashMap();

        for (Element element : elements) {
            if (element.getNodeType() == Node.ELEMENT_NODE) {
                map.put(element.getLocalName(), element.getFirstChild().getNodeValue());
            }
        }

        return map;
    }
}