package org.example.rxjava; import io.reactivex.Observable; import io.reactivex.functions.Function; import java.util.ArrayList; import java.util.List; public class App { public static void main (String args[]){ System.out.println("Start of Program"); List someWords = new ArrayList(); someWords.add("Word1"); someWords.add("Word2"); Observable.fromIterable(someWords) .filter(word -> word.equals("Word1")) .subscribe(word -> System.out.println(word)); } }