### Question:
AggregatedCascade implements Cascade { @Override public void addToggleListener(NodeToggleListener listener) { for (Cascade cascade : cascades) { cascade.addToggleListener(listener); } }  @Override void colorNode(String nodeId, RGBColor fillColor); @Override void addTo(PolygonPanel panel); @Override void addToggleListener(NodeToggleListener listener); @Override void removeToggleListener(NodeToggleListener listener); @Override void initNodeNames(NodePresentationProperties properties); @Override void determinePositionFor(String nodeId, ShapeWithPosition control); void add(ContainerCascade cascade);  }### Answer:
@Test public void addsListenersToAllChildren() throws Exception { NodeToggleListener listener = mock(NodeToggleListener.class); cascade.addToggleListener(listener); verify(child).addToggleListener(listener); }