### Question:
StringUtils { public static String uncapitalize(String str) { return changeFirstCharacterCase(str, false); } private  StringUtils(); static boolean isEmpty(String str); static Predicate<String> notEmpty(); static boolean isEmpty(List<String> list); static String diff(String str1, String str2); static String getFirstFound(String contents, String regex); static String addDefaultPortIfMissing(String urlString); static String addDefaultPortIfMissing(String urlString, String defaultPort); static String capitalize(String name); static String uncapitalize(String str); static byte[] toBytesUTF8(String str); static byte[] toBytesASCII(String str); static byte[] toBytes(String str, String enc); static String toHexString(byte[] bytes);  }### Answer:
@Test public void testUncapitalize() { assertEquals(null, StringUtils.uncapitalize(null)); assertEquals("", StringUtils.uncapitalize("")); assertEquals("a", StringUtils.uncapitalize("A")); assertEquals("a", StringUtils.uncapitalize("a")); assertEquals("aa", StringUtils.uncapitalize("aa")); assertEquals("aa", StringUtils.uncapitalize("Aa")); assertEquals("aA", StringUtils.uncapitalize("AA")); }