Learning RxJava - Second Edition

Fixed-size windowing

Let's modify our earlier example, where we buffered 50 integers into lists of size 8. This time, we will use the window() operator to buffer elements of each list as an Observable. We can reactively transform each batch into something else besides a collection. For example, we can concatenate emissions into strings using a pipe (|), as a separator, as shown in the following code:

import io.reactivex.rxjava3.core.Observable;public class Ch7_08 {    public static void main(String[] args) {        Observable.range(1, 50)                .window(8)                .flatMapSingle(obs -> obs.reduce("", (total, next) ->                         total + (total.equals("") ? "" : "|") + next))                .subscribe(System.out::println);    }}

The output is as follows:

1|2|3|4|5|6|7|89|10|11|12|13|14|15|16 ...