### Question:
ArrayListBackedAggregator extends AbstractListBackedAggregator<T> { @Override protected List<T> createList() { return new ArrayList<T>(); } ArrayListBackedAggregator(Function<List<T>, T> aggregationFunction);  ArrayListBackedAggregator(Function<List<T>, T> aggregationFunction, long interval);  ArrayListBackedAggregator(Function<List<T>, T> aggregationFunction, long interval,
            boolean useSharedTimer); @Override String toString();  }### Answer:
@Test public void testCreateList() throws Exception { @SuppressWarnings("unchecked") ArrayListBackedAggregator<Object> fct = (ArrayListBackedAggregator<Object>) makeFunctor(); assertNotNull(fct.getSeries()); assertTrue(fct.getSeries() instanceof ArrayList); assertEquals(fct.getSeries().size(), 0); int initialSize = 31; fct = new ArrayListBackedAggregator<Object>(new SelectFirstFunction<Object>(), initialSize); assertNotNull(fct.getSeries()); assertTrue(fct.getSeries() instanceof ArrayList); assertEquals(fct.getSeries().size(), 0); }