title: Difference between java HH:mm and hh:mm on SimpleDateFormat
body: <p>Whats the difference between kk:mm, HH:mm and hh:mm formats ??</p>
  
  <pre><code>    SimpleDateFormat broken = new SimpleDateFormat("kk:mm:ss");
      broken.setTimeZone(TimeZone.getTimeZone("Etc/UTC"));
      SimpleDateFormat working = new SimpleDateFormat("HH:mm:ss");
      working.setTimeZone(TimeZone.getTimeZone("Etc/UTC"));
      SimpleDateFormat working2 = new SimpleDateFormat("hh:mm:ss");
      working.setTimeZone(TimeZone.getTimeZone("Etc/UTC"));
  
      System.out.println(broken.format(epoch));
      System.out.println(working.format(epoch));
      System.out.println(working2.format(epoch));
  </code></pre>
  
  <p>prints:</p>
  
  <pre><code>24:00:00
  00:00:00
  05:30:00
  </code></pre>