title: Why does the JFrame setSize() method not set the size correctly?
body: <p>So I've been programming in java for a semester or so, and I've had this problem a few times and finally got around to asking.</p>
  
  <p>If I make a <code>JFrame</code> and then set the size, like <code>setSize(400,800)</code> for example. The frame is not actually <code>800 pixels</code> long. From what I can tell it is actually more like <code>770 (or maybe 769) pixels</code> long. Also, if you set the vertical size very low (below 30), the frame doesn't even show up, only the top window bar from the OS and the frame doesn't get bigger until you go to a value over 30 (so <code>setSize(400,0)</code> looks the same as <code>setSize(400,20)</code>). Why is this, it's not hard to fix but its weird and I'm curious why this is?</p>
  
  <p>If you need more information about anything just ask and I'll get it to you.  </p>