title: Validating Date - Bean validation annotation - With a specific format
body: <p>I would like to validate a Date for the format <code>YYYY-MM-DD_hh:mm:ss</code></p>
  
  <pre><code>@Past //validates for a date that is present or past. But what are the formats it accepts
  </code></pre>
  
  <p>If thats not possible, I would like to use <code>@Pattern</code>. But what is the <code>regex</code> for the above format to use in <code>@Pattern</code>?</p>