### Question:
SensorLabelInteractor extends Interactor { @NonNull @VisibleForTesting String[] generateWeekLabels(@NonNull final Calendar calendar) { final String[] labels = new String[7]; final SimpleDateFormat dateFormat = new SimpleDateFormat("EEE", Locale.getDefault()); for (int i = 0; i < labels.length; i++) { calendar.add(Calendar.DATE, 1); final String day = dateFormat.format(calendar.getTime()); labels[i] = day.toUpperCase(); } return labels; }  @NonNull String[] getWeekLabels(); @NonNull String[] getDayLabels();  }### Answer:
@Test public void hasCorrectWeekLabels() { final String[] labels = sensorLabelInteractor.generateWeekLabels(getCalendar()); assertEquals(labels.length, 7); }