### Question:
PendingResultsHolder { public String create() { final String id = randomId(); pendingResults.put(id, new PendingResult()); return id; }  String create(); void remove(final String id); PendingResult get(final String id);  }### Answer:
@Test public void shouldReturnId_onCreate() { final String id = pendingResultsHolder.create(); assertNotNull(id); }