title: JOptionPane showConfirmDialog with only one button
body: <p>I need to have only one button in <code>showConfirmDialog</code>.</p>
  
  <p>I tried this:</p>
  
  <pre><code>int response = JOptionPane.showConfirmDialog(null, "Time Entered Successfully",
                     "", JOptionPane.OK_OPTION, JOptionPane.PLAIN_MESSAGE);
  
  if (response == JOptionPane.CLOSED_OPTION || response == JOptionPane.OK_OPTION)
  {
     System.out.println("CLOSING&gt;&gt;&gt;&gt;&gt;&gt;");
  }
  </code></pre>
  
  <p>But this shows dialog with Yes_No_option. </p>
  
  <p>I want only OK button to be displayed there. Is it possible?</p>