Modify to use JEditorPane with an HTML kit, so that images (etc.) can be incorporated.
Note that HTML should be styled to have black background, white text and large font for readability:

e.g.
<style type="text/css">
body {
  background-color: black;
  color: white;
  font-family: sans-serif;
  font-weight: bold;
  font-size: 150%;
}
</style>