### Question:
AbstractIndicator implements Indicator<T> { @Override public TimeSeries getTimeSeries() { return series; } AbstractIndicator(TimeSeries series); @Override TimeSeries getTimeSeries(); @Override String toString();  }### Answer:
@Test public void getTimeSeries() { ClosePriceIndicator cp = new ClosePriceIndicator(series); assertEquals(series, cp.getTimeSeries()); SMAIndicator sma = new SMAIndicator(cp, 3); assertEquals(series, sma.getTimeSeries()); }