code: public void setSDef(String sDefPID) throws IOException {
          removeAll();
          if (sDefPID != null) {
              JPanel lp = m_loadedPanels.get(sDefPID);
              if (lp == null) {
                  lp = makePanel(sDefPID);
                  m_loadedPanels.put(sDefPID, lp);
              }
              add(lp, BorderLayout.CENTER);
          }
          if (m_containerToValidate != null) {
              m_containerToValidate.revalidate();
              m_containerToValidate.repaint(new Rectangle(m_containerToValidate
                      .getSize()));
          }
      }
docs: Switch what is displayed (if anything) with information for the indicated
  service definition. If null is given, clear what is currently displayed.