public synchronized void unregisterListener(Listener listener, String viewName, String viewVersion) {

    String name = viewVersion == null ? viewName : ViewEntity.getViewName(viewName, viewVersion);

    Set<Listener> listeners = this.listeners.get(name);

    if (listeners != null) {
      listeners.remove(listener);
    }
  }
Un-register the given listener from the view identified by the given name and version.

@param listener    the listener
@param viewName    the view name
@param viewVersion the view version; null indicates all versions
ambari-server/src/main/java/org/apache/ambari/server/view/ViewRegistry.java