简单XML反序列化具有相同名称的不同元素类型

Question

I'm trying to deserialize this snippet of XML in Java:

<anime id="16986">
    <info type="Picture" src="http://~.jpg" width="141" height="200">
        <img src="http://~" width="141" height="200"/>
        <img src="http://~" width="318" height="450"/>
    </info>
    <info type="Main title" lang="EN">Long Riders!</info>
    <info type="Alternative title" lang="JA">ろんぐらいだぁす！</info>
</anime>

The problem I'm running into is that the info element either can have an inline list of img 's or it can just contain text. I was thinking of treating info as an @Element in my AnimeHolder class, but I can't have duplicate annotations. I would also like to access the lang attribute of info to check if it is EN or JP.

I am using these classes to hold the deserialized data:

@Root(name="anime", strict=false)
public class AnimeHolder {

    @Attribute(name="id")
    private String ANNID;

    @ElementList(inline=true)
    private List<InfoHolder> infoList;

    public String getANNID() {
        return ANNID;
    }

    public List<InfoHolder> getInfoList() {
        return infoList;
    }
}

and for the info items:

@Root(name="info", strict = false)
public class InfoHolder {

    @ElementList(inline=true, required = false)
    private List<ImgHolder> imgList;

    @Attribute(name = "lang", required = false)
    private String language;

    public List<ImgHolder> getImgList() {
        return imgList;
    }
}

Answer 1

With Andreas' I found out I needed to look into handling mixed content. Doing some searching lead me to this solution about creating a custom Converter . After writing my own and finding out it wasn't being called, this helped sort it out. Here is my re-worked InfoHolder class and converter:

@Root(name="info", strict = false)
@Convert(InfoHolder.InfoConverter.class)
public class InfoHolder {

    private String englishTitle;
    private String imageURL;

    static class InfoConverter implements Converter<InfoHolder> {
        @Override
        public InfoHolder read(InputNode node) throws Exception {
            String value = node.getValue();
            InfoHolder infoHolder = new InfoHolder();

            if (value == null){
                InputNode nextNode = node.getNext();
                while (nextNode != null){
                    String tag = nextNode.getName();

                    if (tag.equals("img") && nextNode.getAttribute("src") != null){
                        infoHolder.imageURL = nextNode.getAttribute("src").getValue();
                    }
                    nextNode= node.getNext();
                }
            } else {
                while (node != null){
                    if (node.getAttribute("lang") != null){
                        if (node.getAttribute("lang").getValue().equals("EN")){
                            infoHolder.englishTitle = value;
                            break;
                        }
                    }
                    node = node.getNext();
                }
            }

            return infoHolder;
        }

        @Override
        public void write(OutputNode node, InfoHolder value) throws Exception {

        }
    }
}

I also needed to instantiate a SimpleXmlConverterFactory with a Serializer using AnnotationStrategy like so:

SimpleXmlConverterFactory factory = SimpleXmlConverterFactory.create(new Persister(new AnnotationStrategy()));

Using a custom Converter exposed the XML nodes, which allowed me to figure out if the info node had img children, and if not, get the node value itself.