private void changeNodeState(final CheckedTreeNode node, final boolean checked) {
    if (node.isChecked() != checked) {
      myEventDispatcher.getMulticaster().beforeNodeStateChanged(node);
      node.setChecked(checked);
      myEventDispatcher.getMulticaster().nodeStateChanged(node);
    }
  }
private void changeNodeState(final CheckedTreeNode node, final boolean checked)