code: public void remove(JDesktopPaneLayout child)
      {
          if (child.parent != this)
          {
              throw new IllegalArgumentException(
                  "Layout is not a child of this layout");
          }
          container.remove(child.container);
      }
docs: Remove the given child layout
  
  @param child The child to remove
  @throws IllegalArgumentException If the given child was not
  created by calling {@link #createChild()} on this layout