### Question:
StringUtil { @SuppressWarnings("CStyleArrayDeclaration") public static String decapitalize(String text) { if (isNullOrEmpty(text)) { return text; } char chars[] = text.toCharArray(); chars[0] = Character.toLowerCase(chars[0]); return new String(chars); }  @SuppressWarnings("CStyleArrayDeclaration") static String capitalize(String text); @SuppressWarnings("CStyleArrayDeclaration") static String decapitalize(String text); static String fromSnakeCaseToCamelCase(String text); static String fromCamelCaseToSnakeCase(String text); static String fromCamelCaseToSnakeCaseWithLenient(String text); static boolean isWhitespace(String text); static String trimWhitespace(String text);  }### Answer:
@Test public void testDecapitalize() { assertEquals("aAA", StringUtil.decapitalize("AAA")); }