@Test
public void testJoin() {

  final String[] a = new String[] {"a", "b"};
  final String j1 = StringUtil.join(a, ", ");
  assertEquals("a, b", j1);
  final List<String> s = new ArrayList<String>();
  s.add("1");
  s.add("2");
  final String j2 = StringUtil.join(s, ", ");
  assertEquals("1, 2", j2);
}