Learning RxJava

toSortedList()

A different flavor of toList() is toSortedList(). This will collect the emissions into a list that sorts the items naturally based on their Comparator implementation. Then, it will emit that sorted List<T> forward to the Observer:

import io.reactivex.Observable;public class Launcher {      public static void main(String[] args) {        Observable.just(6, 2, 5, 7, 1, 4, 9, 8, 3)          .toSortedList()          .subscribe(s -> System.out.println("Received: " + s));     }}

The output of the preceding code snippet is as follows:

Received: [1, 2, 3, 4, 5, 6, 7, 8, 9]

Like sorted(), you can provide a Comparator as an argument to apply a different sorting logic. You can also specify an initial capacity for the backing ArrayList just like toList().