### Question:
Util { public static int compare(@Nullable String s1, @Nullable String s2) { if (s1 == s2) { return 0; } else if ((s1 == null) && (s2 != null)) { return -1; } else if ((s1 != null) && (s2 == null)) { return 1; } return s1.compareTo(s2); }  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 testCompare() throws Exception { assertTrue(Util.compare("foo", "bar") > 1); assertTrue(Util.compare("bar", "foo") < 1); assertEquals(0, Util.compare("foo", "foo")); assertEquals(-1, Util.compare(null, "foo")); assertEquals(1, Util.compare("foo", null)); assertEquals(0, Util.compare(null, null)); }