Timer task in RxJava kotlin/java

RxJavaTimerTask.kt

val subscription = Observable.interval(0, 5, TimeUnit.SECONDS)
                    .timeInterval()
                    .observeOn(AndroidSchedulers.mainThread())
                    .subscribeOn(Schedulers.io())
                    .subscribe { 
                      //TODO 
                    }

TimerTask.java

Disposable timerTaskSubscription = Observable.interval(0, 30, TimeUnit.SECONDS)
                    .observeOn(AndroidSchedulers.mainThread())
                    .subscribeOn(Schedulers.io())
                    .subscribe(new Consumer<Long>() {
                                   @Override
                                   public void accept(Long aLong) throws Exception {
                                       //TODO onNext
                                   }
                               },
                            new Consumer<Throwable>() {
                                @Override
                                public void accept(Throwable throwable) throws Exception {
                                    //TODO onError
                                }
                            });