@Test public void testEmptyAvg() { DoubleStat avg = new DoubleStat(); assertNull(avg.getAvg()); }
Double getAvg() { return count == 0 ? null : getSum() / count; }
DoubleStat { Double getAvg() { return count == 0 ? null : getSum() / count; } }
DoubleStat { Double getAvg() { return count == 0 ? null : getSum() / count; }  }
DoubleStat { Double getAvg() { return count == 0 ? null : getSum() / count; }   }
DoubleStat { Double getAvg() { return count == 0 ? null : getSum() / count; }    }