@Override
    public void writeCharacters(char[] text, int start, int len) throws XMLStreamException {
        nonXmlCharFilterer.filter(text, start, len);
        writer.writeCharacters(text, start, len);
    }
@Test
    public void testWriteCharacters1Arg() throws XMLStreamException {
        filteringXmlStreamWriter.writeCharacters("value");
        verify(xmlStreamWriterMock).writeCharacters("filteredValue");
    }