title: using regular expression: validate email address
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/201323/what-is-the-best-regular-expression-for-validating-email-addresses">What is the best regular expression for validating email addresses?</a>  </p>
  </blockquote>
  
  
  
  <p>Hi I'm a newbie about the using of regular expression
  I have this regular expression to validate an mail but I don't understand the meaning.Someone could explain me?</p>
  
  <pre><code>mailPattern = Pattern.compile("[a-zA-Z_0-9]*[.[a-zA-Z_0-9]*]*@[a-zA-Z_0-9]*[.[a-zA-Z_0-9]*]*.[a-zA-Z]{2,3}");
  </code></pre>