### Question:
Util { public static String oxfordComma(String conjuction, Object... list) { StringBuilder rv = new StringBuilder(); for (int ii = 0; ii < (list.length - 1); ++ii) { if (ii > 0) rv.append(", "); rv.append(list[ii]); } if (list.length > 1) { if (conjuction == null) { rv.append(", "); } else { if (list.length > 2) rv.append(","); rv.append(" ").append(conjuction).append(" "); } } rv.append(list[list.length - 1]); return rv.toString(); }  static void setContextAndConfig(Context context, GameConfiguration config); static Context getContext(); static GameConfiguration getConfig(); static int compare(@Nullable String s1, @Nullable String s2); static String oxfordComma(String conjuction, Object... list); static T find(Collection<T> list, Requirement<T> test); static String join(String delimiter, Iterable it); static boolean isDeveloper(Context context);  }### Answer:
@Test public void testOxfordComma() throws Exception { assertEquals("foo", Util.oxfordComma("or", "foo")); assertEquals("foo or bar", Util.oxfordComma("or", "foo", "bar")); assertEquals("foo, bar, or baz", Util.oxfordComma("or", "foo", "bar", "baz")); assertEquals("foo, bar, baz, or blurfl", Util.oxfordComma("or", "foo", "bar", "baz", "blurfl")); assertEquals("foo", Util.oxfordComma(null, "foo")); assertEquals("foo, bar", Util.oxfordComma(null, "foo", "bar")); assertEquals("foo, bar, baz", Util.oxfordComma(null, "foo", "bar", "baz")); assertEquals("foo, bar, baz, blurfl", Util.oxfordComma(null, "foo", "bar", "baz", "blurfl")); }