### Question:
SessionPreviewCanvasHandlerProxy extends BaseCanvasHandler<D, C> { @Override public CanvasHandler<D, C> doClear() { return wrapped.doClear(); } @SuppressWarnings("unchecked")  SessionPreviewCanvasHandlerProxy(final BaseCanvasHandler wrapped,
                                            final DefinitionManager definitionManager,
                                            final GraphUtils graphUtils,
                                            final ShapeManager shapeManager,
                                            final TextPropertyProviderFactory textPropertyProviderFactory); BaseCanvasHandler getWrapped(); @Override GraphCommandExecutionContext getGraphExecutionContext(); @Override RuleManager getRuleManager(); @Override Index<?, ?> getGraphIndex(); @Override DefinitionManager getDefinitionManager(); @Override TextPropertyProviderFactory getTextPropertyProviderFactory(); @Override void register(final Shape shape,
                         final Element<View<?>> candidate,
                         final boolean fireEvents); @Override void register(final String shapeSetId,
                         final Element<View<?>> candidate); @Override void register(final ShapeFactory<Object, Shape> factory,
                         final Element<View<?>> candidate,
                         final boolean fireEvents); @Override void deregister(final Shape shape,
                           final Element element,
                           final boolean fireEvents); @Override void deregister(final Element element); @Override void deregister(final Element element,
                           final boolean fireEvents); @Override void addChild(final Element parent,
                         final Element child); @Override void addChild(final Element parent,
                         final Element child,
                         final int index); @Override void removeChild(final Element parent,
                            final Element child); @Override Optional<Element> getElementAt(final double x,
                                          final double y); @Override boolean dock(final Element parent,
                        final Element child); @Override void undock(final Element parent,
                       final Element child); @Override CanvasHandler<D, C> clear(); @Override CanvasHandler<D, C> doClear(); @Override void destroy(); @Override void doDestroy(); @Override void applyElementMutation(final Shape shape,
                                     final Element candidate,
                                     final boolean applyPosition,
                                     final boolean applyProperties,
                                     final MutationContext mutationContext); @Override void applyElementMutation(final Element element,
                                     final MutationContext mutationContext); @Override void updateElementPosition(final Element element,
                                      final MutationContext mutationContext); @Override void updateElementProperties(final Element element,
                                        final MutationContext mutationContext); @Override void applyElementMutation(final Element candidate,
                                     final boolean applyPosition,
                                     final boolean applyProperties,
                                     final MutationContext mutationContext); @Override ShapeFactory<Object, Shape> getShapeFactory(final String shapeSetId); @Override CanvasHandler<D, C> handle(final C canvas); @Override void draw(final ParameterizedCommand<CommandResult> loadCallback); @Override void draw(final D diagram,
                     final ParameterizedCommand<CommandResult> loadCallback); @Override D getDiagram(); @Override C getCanvas(); @Override HasCanvasListeners<CanvasElementListener> addRegistrationListener(final CanvasElementListener instance); @Override HasCanvasListeners<CanvasElementListener> removeRegistrationListener(final CanvasElementListener instance); @Override HasCanvasListeners<CanvasElementListener> clearRegistrationListeners(); @Override void notifyCanvasElementRemoved(final Element candidate); @Override void notifyCanvasElementAdded(final Element candidate); @Override void notifyCanvasElementUpdated(final Element candidate); @Override void notifyCanvasClear(); @Override void clearCanvas(); @Override AbstractCanvas getAbstractCanvas(); @Override boolean isCanvasRoot(final Element parent); @Override String getUuid(); @Override boolean equals(Object o); @Override int hashCode(); @Override String toString();  }### Answer:
@Test public void checkDoClearDelegatesToWrapped() { proxy.doClear(); verify(wrapped).doClear(); }