XStream : node with attributes and text node in xstream 1.3.1?

Question

I would like to serialize an object to an XML of this form with XStream.

<node att="value">text</node>

There already is a solution for this in StackOverflow here: XStream : node with attributes and text node? but it won't work for me since I am restricted to XStream 1.3.1.

I found

@XStreamConverter(value=ToAttributedValueConverter.class, strings={"content"}) 

which does exactly what I want in a simple way but it is not available in XStream 1.3.1.

Is there a nicer way to solve this issue with 1.3.1 version of XStream?

Answer 1

It's possible with some hacks. The main idia is to use a modified ToAttributedValueConverter from 1.4.7.

1. Copy ToAttributedValueConverter into your package
2. Copy UseAttributeForEnumMapper into your package

3. Replace ToAttributedValueConverter#fieldIsEqual as follows:

   private boolean fieldIsEqual(FastField field) {
       return valueField.getName().equals(field.getName())
               && valueField.getDeclaringClass().getName()
                       .equals(field.getDeclaringClass().getName());
   }
   

4. Replace the Constructor in UseAttributeForEnumMapper as follows:

   public UseAttributeForEnumMapper(Mapper wrapped) {
       super(wrapped, null);
   }
   

It is not possible to use the @XStreamConverter annotation, becouse the ToAttributedValueConverter has a constrcutor that needs some extra information, like the value field. But you can use XStream#registerConverter alternativly. So your class have to look like:

    @XStreamAlias("node")
    public class Node {
        private String attr;
        private String content;

        public void setAttr(String attr) { this.attr = attr; }
        public String getAttr() { return attr; }
        public void setContent(String content) { this.content = content; }
        public String getContent() { return content; }
    }

And a example that shows how to configure xstream for this converter:

    public static void main(String[] args) {
        final Node node = new Node();
        node.setAttr("value");
        node.setContent("text");

        final XStream xstream = new XStream();
        configureXStream(xstream);

        final String xml = xstream.toXML(node);
        System.out.println(xml);

        final Node node2 = (Node) xstream.fromXML(xml);
        System.out.println("attr: " + node2.getAttr());
        System.out.println("content: " + node2.getContent());
    }

    private static void configureXStream(final XStream xstream) {
        xstream.autodetectAnnotations(true);
        final Mapper mapper = xstream.getMapper();
        final ReflectionProvider reflectionProvider = xstream
                .getReflectionProvider();
        final ConverterLookup lookup = xstream.getConverterLookup();
        final Converter converter = new ToAttributedValueConverter(Node.class,
                mapper, reflectionProvider, lookup, "content");
        xstream.registerConverter(converter);
    }

This program prints out:

    <node attr="value">text</node>
    attr: value
    content: text