### Question:
ChangesMapOperation extends AbstractGraphOperation<MapResult<String, Set<String>>> { @Override public MapResult<String, Set<String>> execute(Graph<Vertex, Edge> graph) { return new MapResult<>(changes.stream().collect(toMapActorAction)); } ChangesMapOperation(Set<Vertex> changes); @Override MapResult<String, Set<String>> execute(Graph<Vertex, Edge> graph);  }### Answer:
@Test public void execute() { ChangesMapOperation changesMapOperation = new ChangesMapOperation(graphOperations.getChanges()); MapResult<String, Set<String>> result = changesMapOperation.execute(builder.getGraph()); Map<String, Set<String>> changesMap = result.get(); assertNotNull(changesMap); assertEquals(1, changesMap.size()); Set<String> classA = changesMap.get("ClassA"); assertNotNull(classA); assertEquals(2, classA.size()); assertTrue(classA.contains("coveredMethod()")); assertTrue(classA.contains("uncoveredMethod()")); }