### Question:
StringConverter { public static String integersAsString(Collection<Integer> ids) { List<Integer> idList = new ArrayList<Integer>(ids); return integersAsString(idList); }  static String commaSeperatedStringList(List<String> strList); static String getExtendedStackTrace(Throwable ti); static String getStackTrace(Exception ex); static String integersAsString(Collection<Integer> ids); static String integersAsString(List<Integer> ids);  }### Answer:
@Test public void testEmptyString() { assertEquals(emptyString, StringConverter.integersAsString(emptyList)); }
@Test public void testOneString() { assertEquals(oneInString, StringConverter.integersAsString(oneInList)); }
@Test public void testThreeString() { assertEquals(threeInString, StringConverter.integersAsString(threeInList)); }