### Question:
CharacterFilterUtils { public static String filterInvalidXmlCharacters(final String value) { if (value == null) { return null; } return INVALID_XML_CHARACTER_FILTER.translate(value); }  static String filterInvalidXmlCharacters(final String value);  }### Answer:
@Test public void filterInvalidCharacters() throws Exception { final String text = "This is an example with characters that need to be filtered \u0002 in it. " + Character.MIN_SURROGATE; final String filtered = CharacterFilterUtils.filterInvalidXmlCharacters(text); final String expected = "This is an example with characters that need to be filtered in it. "; Assert.assertEquals(expected, filtered); }