@Test
public void testInvalidCharacters() throws SAXException {

    safe.characters("ab\u0007".toCharArray(), 0, 3);
    safe.characters("a\u000Bc".toCharArray(), 0, 3);
    safe.characters("\u0019bc".toCharArray(), 0, 3);
    assertEquals("ab\ufffda\ufffdc\ufffdbc", output.toString());
}