code: private Node getNode(final Wave wave) {
          Node node = waveBean(wave).node();
  
          if (node == null && wave.hasWaveBean(DisplayModelWaveBean.class)) {
              node = wave.waveBean(DisplayModelWaveBean.class).showModel().node();
          }
          return node;
      }
docs: Gets the node.
  
  @param wave the wave
  @return the node