@Override
  public void addListener(final IZyNodeRealizerListener<? extends ZyGraphNode<?>> listener) {
    m_listeners.addListener(listener);
  }
Listeners that are notified about changes in the node realizer.
java/zylib/src/main/java/com/google/security/zynamics/zylib/yfileswrap/gui/zygraph/realizers/ZyGroupNodeRealizer.java