title: Difference between \uXXXX, \uuXXXX and \uuuXXXX
body: <p>Following line is from <a href="https://docs.oracle.com/javase/specs/jls/se8/html/jls-3.html#jls-3.3" rel="nofollow noreferrer">JLS §3.3</a>:</p>
  <blockquote>
  <p>If an eligible \ is followed by u , <strong>or more than one u</strong> , and the last u is not followed
  by four hexadecimal digits, then a compile-time error occurs.</p>
  </blockquote>
  <p>So this means the following lines will result the same:</p>
  <pre><code>System.out.println('\u0065');   // prints &quot;e&quot;
  System.out.println('\uu0065');  // prints &quot;e&quot;
  System.out.println('\uuu0065'); // prints &quot;e&quot;
  </code></pre>
  <p>Using a single <code>u</code> in <code>\uXXXX</code> essentially does the same as using <code>uu</code> in <code>\uuXXXX</code>. My question is, why do we need this kind of design?</p>