Receive notification of a processing instruction.
The Parser will invoke this method once for each processing instruction found: note that processing instructions may occur before or after the main document element.
A SAX parser must never report an XML declaration (XML 1.0, section 2.8) or a text declaration (XML 1.0, section 4.3.1) using this method.
Like {@link #characters characters()}, processing instruction data may have characters that need more than one char
value.
@param target the processing instruction target
@param data the processing instruction data, or null ifnone was supplied. The data does not include any whitespace separating it from the target
@throws org.xml.sax.SAXException any SAX exception, possiblywrapping another exception