title: class file for org.reactivestreams.Publisher not found while compiling example from RxJava?
body: <p>The following code</p>
  
  <pre><code>package com.inthemoon.snippets.rxjava;
  
  import io.reactivex.*;
  
  public class HelloWorld {
  
     public static void main(String[] args) {
        Flowable.just("Hello world").subscribe(System.out::println);
     }
  
  }
  </code></pre>
  
  <p>causes the following compile error</p>
  
  <p>Error:(9, 15) java: cannot access org.reactivestreams.Publisher
    class file for org.reactivestreams.Publisher not found</p>
  
  <p>POM dependency is following</p>
  
  <pre><code>&lt;dependencies&gt;
          &lt;!-- https://mvnrepository.com/artifact/io.reactivex.rxjava2/rxjava --&gt;
          &lt;dependency&gt;
              &lt;groupId&gt;io.reactivex.rxjava2&lt;/groupId&gt;
              &lt;artifactId&gt;rxjava&lt;/artifactId&gt;
              &lt;version&gt;2.0.4&lt;/version&gt;
          &lt;/dependency&gt;
  
  
      &lt;/dependencies&gt;
  </code></pre>