title: Java character input validation
body: <p>I want to validate a single character in a java application.
  I don't want the user to be able to enter a character outside the range <code>[a - p]</code> (ignoring uppercase or lowercase) or <code>numbers</code>. </p>
  
  <pre><code>Scanner input = new Scanner(System.in);
  
  System.out.print("Choose letter in range [a - p]");
  letter = input.next().charAt(0);
  </code></pre>
  
  <p>Any ideas? </p>