How to deserialize using XStream?

Question

    <PlayListSettings>
        <PlayList>
          <id>PlayList1</Name>
          <File class="string">/mnt/sdcard/Video1</File>
        </PlayList>
     </PlayListSettings>

This is my Serialized xml,where File is an arrayList of strings. I could remove the class="string" using xstream.aliasSystemAttribute(null, "class");

 and the output is 
<PlayListSettings>
        <PlayList>
          <id>PlayList1</Name>
          <File>/mnt/sdcard/Video1</File>
        </PlayList>
     </PlayListSettings>

How do i deserialize using XStream?

Answer 1

You can use the @XStreamImplicit annotation for it. Here is a fully working example:

@XStreamAlias("PlayList")
public final class PlayList {
    @XStreamImplicit(itemFieldName = "File")
    private final List<String> files = new ArrayList<>();

    public void addFile(final String file) {
        checkFile(file);
        files.add(file);
    }

    public void removeFile(final String file) {
        checkFile(file);
        files.remove(file);
    }

    public List<String> getFiles() {
        return Collections.unmodifiableList(files);
    }

    private void checkFile(final String file) {
        if (file == null) {
            throw new NullPointerException();
        } else if (file.isEmpty()) {
            throw new IllegalArgumentException("is empty");
        }
    }

    public static void main(String[] args) {
        final PlayList playList = new PlayList();
        playList.addFile("Foo");
        playList.addFile("Bar");

        // Serialize
        final XStream xstream = new XStream();
        xstream.autodetectAnnotations(true);
        final String xml = xstream.toXML(playList);
        System.out.println(xml);

        // Deserialize
        final PlayList playList2 = (PlayList) xstream.fromXML(xml);
        for (final String file : playList.getFiles()) {
            System.out.println(file);
        }
    }
}

The output looks like:

<PlayList>
  <File>Foo</File>
  <File>Bar</File>
</PlayList>