### Question:
SchoolYearConverter { public String convert(Integer schoolYear) { if (schoolYear == null) { return null; } Integer priorSchoolYear = schoolYear - 1; return priorSchoolYear.toString() + "-" + schoolYear.toString(); }  String convert(Integer schoolYear);  }### Answer:
@Test public void testNullList() { String result = converter.convert(null); Assert.assertNull("school year should be null", result); }
@Test public void test() { Assert.assertEquals(converter.convert(2011), "2010-2011"); Assert.assertEquals(converter.convert(2013), "2012-2013"); }