title: Identify which of three partially overlapping images is clicked
body: <p>I have several JLabels, each holding an ImageIcon like this:</p>
  
  <pre><code>ImageIcon icon = new ImageIcon("path/to/image.jpg");
  JLabel label = new JLabel(icon);
  </code></pre>
  
  <p>Those images are .PNGs in a hexagonal shape. The edges "outside" the hexagon (the redundant part that exists is using a rectangular canvas) are transparent.
  The JLabels, ergo the images, are ordered like <a href="http://upload.wikimedia.org/wikipedia/commons/d/dd/Hexagons.jpg" rel="nofollow">in this example</a>, so there are always three interfering images.</p>
  
  <p>Since there is no "visible" layer beneath or over an other, I want to define the "clickable area" to exactly the visible layer. What is the cleverest way to do so, or is there an even more elegant solution?</p>