title: Stream of maps to map
body: <p>How can I flatten a <code>Stream</code> of <code>Map</code>s (of the same types) to a single <code>Map</code> in Java 8?</p>
  
  <pre><code>Map&lt;String, Long&gt; toMap(Stream&lt;Map&lt;String, Long&gt;&gt; stream) {
      return stream. ???
  }
  </code></pre>