Learning RxJava

distinctUntilChanged()

The distinctUntilChanged() function will ignore duplicate consecutive emissions. It is a helpful way to ignore repetitions until they change. If the same value is being emitted repeatedly, all the duplicates will be ignored until a new value is emitted. Duplicates of the next value will be ignored until it changes again, and so on. Observe the output for the following code to see this behavior in action:

 

import io.reactivex.Observable;public class Launcher {      public static void main(String[] args) {        Observable.just(1, 1, 1, 2, 2, 3, 3, 2, 1, 1)          .distinctUntilChanged()          .subscribe(i -> System.out.println("RECEIVED: " + i));      }}

The output of the preceding code snippet is as follows:

 

RECEIVED: 1RECEIVED: 2RECEIVED: 3 ...