/**
* Creates a new datapoint from XML input.
*
* <p>If the current XML element position is no start tag, the next element tag is read. The
* datapoint element is then expected to be the current element in the reader. It reads the start
* tag and attributes of a datapoint element, and sets the reader to the next position.
*
* @param r a XML reader
* @throws KNXMLException if the XML element is no datapoint or could not be read correctly
*/
Datapoint(final XMLReader r) throws KNXMLException {
if (r.getPosition() != XMLReader.START_TAG) r.read();
final Element e = r.getCurrent();
final int line = r.getLineNumber();
if (r.getPosition() != XMLReader.START_TAG || !e.getName().equals(TAG_DATAPOINT))
throw new KNXMLException("no KNX datapoint element", e != null ? e.getName() : null, line);
stateBased = readDPType(r);
if ((name = e.getAttribute(ATTR_NAME)) == null)
throw new KNXMLException("missing attribute " + ATTR_NAME, null, line);
if ((dptId = e.getAttribute(ATTR_DPTID)) == null)
throw new KNXMLException("missing attribute " + ATTR_DPTID, null, line);
if (dptId.length() == 0) dptId = null;
String a = null;
try {
a = e.getAttribute(ATTR_MAINNUMBER);
mainNo = Integer.decode(a).intValue();
a = e.getAttribute(ATTR_PRIORITY);
priority = Priority.get(a);
} catch (final RuntimeException rte) {
throw new KNXMLException("malformed attribute, " + rte.getMessage(), a, line);
}
r.read();
}
/* returns true for state based DP, false for command based DP */
private static boolean readDPType(final XMLReader r) throws KNXMLException {
final String a = r.getCurrent().getAttribute(ATTR_STATEBASED);
if ("false".equalsIgnoreCase(a)) return false;
if ("true".equalsIgnoreCase(a)) return true;
throw new KNXMLException("malformed attribute " + ATTR_STATEBASED, a, r.getLineNumber());
}