gistfile1.java

// Clearly this won't actually work since obs2 would need to be final but then you can't assign it inside the handler    

MyEventBus eb = new MyEventBus();

    Observable obs1 = eb.send("foo", "msg1");
    Observable obs2;

    obs1.subscribe(new Action1<String>() {
      @Override
      public void call(String str) {
        System.out.println("Got result: " + str);
        obs2 = eb.send("foo", str);
      }
    });
    obs2.subscribe(new Action1<String>() {
      @Override
      public void call(String str) {
        System.out.println("Got result: " + str);
      }
    });