title: How to set the default icon for all Java Swing windows?
body: <p>How to set the default icon for all Java Swing windows?</p>
  
  <p>Otherwise i have to set icons for every frame i created. </p>
  
  <p>What's your suggestions?
  Simple hackings are also accepted.</p>
  
  <p>many thx</p>
  
  <p><strong>Update: Best if the method you suggested can leave existing frame-creation codes untouched. thx</strong></p>