title: How to efficiently merge two lists in Java?
body: <p>There are several ways to merge lists in Java</p>
  <ul>
  <li>You can call to <code>ArrayList(Collection&lt;? extends E&gt; c)</code></li>
  <li>You can use the stream API, like <code>Stream.concat()</code> or <code>Stream.of(listA, listB).forEach()</code></li>
  <li>and more...</li>
  </ul>
  <p>What would be the most memory and performance efficient way to merge two random access lists into a new random access list?</p>