docs: private void adjustTarget(
                               DeleteNode    point)
      {
          int s = point.targetType();
          GBSNode t = point.targetNode();
          GBSNode d = point.deleteNode();
          int    tx;
  
          switch (s)
          {
          case DeleteNode.NONE:
              /* Nothing to do.  Delete point is in a leaf.                       */
              break;
          case DeleteNode.ADD_LEFT:
              /* Migrate up high key of a leaf into its upper successor node.     */
              tx = point.targetIndex();
              t.addLeftMostKeyByDelete(tx, d.rightMostKey());
              break;
          case DeleteNode.ADD_RIGHT:
              /* Migrate up low key of a leaf into its upper predecessor node.    */
              tx = point.targetIndex();
              t.addRightMostKeyByDelete(tx, d.leftMostKey());
              break;
          case DeleteNode.OVERLAY_RIGHT:
              /* Migrate up low key of a leaf into high key of upper predecessor. */
              t.overlayRightMostKey(d.leftMostKey());
              break;
          case DeleteNode.OVERLAY_LEFT:
              /* Migrate up high key of a leaf into low key of upper successor.   */
              t.overlayLeftMostKey(d.rightMostKey());
              break;
          default:
              throw new RuntimeException("s = " + s);
          }
      }