code: private SeaGlassPainter getPainter(TreeMap<String, Object> defaults, String key) {
          Object p = defaults.get(key);
  
          if (p instanceof UIDefaults.LazyValue) {
              p = ((UIDefaults.LazyValue) p).createValue(UIManager.getDefaults());
          }
  
          return (p instanceof SeaGlassPainter ? (SeaGlassPainter) p : null);
      }
docs: Determine the painter given the defaults and a key.
  
  @param  defaults the defaults.
  @param  key      the key.
  
  @return the painter, if any can be found, {@code null} otherwise.