code: void remove(JInternalFrame internalFrame)
      {
          Component component = frameToComponent.get(internalFrame);
          container.remove(component);
      }
docs: Remove the given internal frame from this layout.<br>
  <br>
  Note that this will <b>not</b> remove the internal frame from the
  desktop pane that this layout belongs to!
  
  @param internalFrame The internal frame to remove