@Override
        public void workerEnd(final Stage stage) {
            assertFalse(WORKER_START.isEmpty());
            if (!stage.equals(Stage.MAP))
                assertFalse(WORKER_END.isEmpty());
            WORKER_END.add(stage);
        }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/computer/GraphComputerTest.java