@Override
    public void writeAttribute(String prefix, String namespaceURI, String localName, String value)
            throws XMLStreamException {
        String filteredValue = nonXmlCharFilterer.filter(value);
        writer.writeAttribute(prefix, namespaceURI, localName, filteredValue);
    }
@Test
    public void testWriteAttribute3Args() throws XMLStreamException {
        filteringXmlStreamWriter.writeAttribute("namespaceURI", "localName", "value");
        verify(xmlStreamWriterMock).writeAttribute("namespaceURI", "localName", "filteredValue");
    }