code: private void ensureNodeVisible(TreePath nodePath) {
          Rectangle bounds = getTreeParam().getPathBounds(nodePath);
          if (!getTreeParam().getVisibleRect().contains(bounds)) {
              // Just do vertical scrolling.
              bounds.x = 0;
              getTreeParam().scrollRectToVisible(bounds);
          }
      }
docs: Ensures the node of the panel is visible in the view port.
  <p>
  The node is assumed to be already {@link JTree#isVisible(TreePath) visible in the tree}.
  
  @param nodePath the path to the node of the panel.