### Question:
DestinationAndModelRegistry { public String put(FacesContext context, DestinationAndModel destinationAndModel) { Assert.notNull(destinationAndModel, "DestinationAndModel must not be null"); synchronized (this) { Map<String, DestinationAndModel> container = getContainer(context, true); String key = KEY_PREFIX + String.valueOf(container.size() + 1); container.put(key, destinationAndModel); return key; } }  String put(FacesContext context, DestinationAndModel destinationAndModel); DestinationAndModel get(FacesContext context, String key);  }### Answer:
@Test public void shouldNeedFacesContext() throws Exception { DestinationAndModel d = new DestinationAndModel(new NavigationOutcome(new Object()), (ActionEvent) null); this.thown.expect(IllegalStateException.class); this.registry.put(null, d); }