@Override
  public void dispose() {
    if (myUsagePreviewPanel != null) {
      UsageViewSettings.getInstance().setPreviewUsagesSplitterProportion(((Splitter)myUsagePreviewPanel.getParent()).getProportion());
      myUsagePreviewPanel = null;
    }

    isDisposed = true;
    ToolTipManager.sharedInstance().unregisterComponent(myTree);
  }
@Override
  public void dispose()