void (int newIndex) { if (rollOverIndex >= 0 && rollOverIndex < getModel().getSize()) { JCheckBox oldRollover = getModel().getElementAt(rollOverIndex); oldRollover.getModel().setRollover(false); } rollOverIndex = newIndex; if (rollOverIndex >= 0) { JCheckBox newRollover = getModel().getElementAt(rollOverIndex); newRollover.getModel().setRollover(true); } UIUtil.repaintViewport(this); }