title: How to convert Character array to Set
body: <p>How do I add a list of chars into a set?
  The code below doesn't seem to work.</p>
  
  <pre><code>HashSet&lt;Character&gt; vowels = new HashSet&lt;Character&gt;(
          new Character[] {'a', 'e', 'i', 'o', 'u', 'y'}
      );
  </code></pre>
  
  <p>The error that I'm seeing is</p>
  
  <blockquote>
    <p>The constructor HashSet(Character[]) is undefined</p>
  </blockquote>
  
  <p>I tried both, Character[] and char[], but neither is working.</p>