使用不同类型的内容反序列化XML

Question

我想为现有的JavaScript库（SmartClient）构建一个REST java后端（使用jersey）。这个JavaScript库以不同的格式将请求发送到我的服务器。

如何将XML反序列化为包含不同类型内容的容器对象？

这是一个例子，我已经尝试过：

import java.io.StringReader;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Box {

    static class Ball {
        public String size;
        public String toString() {return "Ball(" + size + ")";}
    }

    static class Cat {
        public String name;
        public String toString() {return "Cat(" + name + ")";}
    }

    public static void main(String[] args) throws Exception {
        printContent("<box><content><size>3</size></content></box>");
        printContent("<box><content><name>Mimi</name></content></box>");
    }

    private static void printContent(String xml) throws JAXBException {
        JAXBContext context = JAXBContext.newInstance(Box.class, Ball.class, Cat.class);
        Unmarshaller unmarshaller = context.createUnmarshaller();
        Box box = (Box) unmarshaller.unmarshal(new StringReader(xml));

        System.out.println(box.content);
    }

    // not working
    public Object content;

    // not working
    // @XmlMixed
    // public Object content;

    // not working
    // @XmlAnyElement
    // public List<Object> content;

    // not working
    // @XmlAnyElement(lax=true)
    // public List<Object> content;

    // not working
    // @XmlJavaTypeAdapter(ContentXmlAdapter.class)
    // public Object content;
    // static class ContentXmlAdapter extends XmlAdapter<String, Object>{
    // 
    //  @Override
    //  public Object unmarshal(String v) throws Exception {
    //      System.out.println("unmarshal("+v+")");
    //      return null;
    //  }
    // 
    //  public String marshal(Object v) throws Exception {throw new UnsupportedOperationException();}
    // }
}