public void testThread() throws Exception {
Abdera abdera = new Abdera();
Factory factory = abdera.getFactory();
Entry e1 = factory.newEntry();
Entry e2 = factory.newEntry();
e1.setId("tag:example.org,2006:first");
e2.setId("tag:example.org,2006:second");
ThreadHelper.addInReplyTo(e2, e1); // e2 is a response to e1