### Question:
DCSeriesNumber { public String getSeries() { return ((series == null) ? "" : series); } DCSeriesNumber();  DCSeriesNumber(String value);  DCSeriesNumber(String s, String n); String toString(); String getSeries(); String getNumber();  }### Answer:
@Test public void testGetSeries() { dc = new DCSeriesNumber(null, null); assertThat("testGetSeries 0", dc.getSeries(), equalTo("")); dc = new DCSeriesNumber("series", null); assertThat("testGetSeries 1", dc.getSeries(), equalTo("series")); }