Learning RxJava

blockingLast()

If there is blockingFirst(), it only makes sense to have blockingLast(). This will block and return the last value to be emitted from an Observable or Flowable operation. Of course, it will not return anything until onComplete() is called, so this is something you will want to avoid using with infinite sources.

Here, we assert that the last four-character string emitted from our operation is Zeta:

 import io.reactivex.Observable; import org.junit.Test; import static org.junit.Assert.assertTrue; public class RxTest {     @Test     public void testLast() {         Observable<String> source =                 Observable.just("Alpha", "Beta", "Gamma", "Delta", "Zeta");         String lastWithLengthFour = source.filter(s -> s.length() == 4)                 .blockingLast(); assertTrue(lastWithLengthFour.equals("Zeta")); ...