@XStreamOmitField isn't omitting a field

This doesn't work; the poolFactory is still showing up in the output:

@XStreamOmitField
private final Factory poolFactory = new Factory() {
public Object create()

};

Adding omitField to the code makes it go away:

public void setUp() throws Exception {
xstream = new XStream();

xstream.setMode(XStream.ID_REFERENCES);

xstream.registerConverter(new CollectionConverter(xstream.getMapper()) {
@Override
public boolean canConvert(final Class type)

});

xstream.omitField(Photo.class, "poolFactory");
}