### Question:
DateFormats { public static void register(String languageCode, String pattern) { LANGUAGE_PATTERNS.put(languageCode, pattern); } private  DateFormats(); static void register(String languageCode, String pattern); static String getPattern(Locale locale); static final String PATTERN_ISO; static final String PATTERN_DE; }### Answer:
@Test public void testRegister() { String customPattern = "yyMMdd"; DateFormats.register("foobar", customPattern); assertThat(DateFormats.getPattern(new Locale("foobar")), is(customPattern)); }