/**
* Returns the nth geometry of a geometry collection.
*
* @param node xml element containing gml object(s)
* @param number index of i-th interior ring
* @return n-th interior ring geometry (LineString) as a gml element
* @throws QueryException query exception
*/
@Deterministic
public ANode interiorRingN(final ANode node, final Int number) throws QueryException {
final Geometry geo = geo(node, Q_GML_POLYGON);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Polygon");
final long n = number.itr();
final int max = ((Polygon) geo).getNumInteriorRing();
if (n < 1 || n > max) throw GeoErrors.outOfRangeIdx(number);
return gmlWriter(((Polygon) geo).getInteriorRingN((int) n - 1));
}
/**
* Returns the nth point of a line.
*
* @param node xml element containing gml object(s)
* @param number index of i-th point
* @return n-th point as a gml element
* @throws QueryException query exception
*/
@Deterministic
public ANode pointN(final ANode node, final Int number) throws QueryException {
final Geometry geo = geo(node, Q_GML_LINEARRING, Q_GML_LINESTRING);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Line");
final int max = geo.getNumPoints();
final long n = number.itr();
if (n < 1 || n > max) throw GeoErrors.outOfRangeIdx(number);
return gmlWriter(((LineString) geo).getPointN((int) n - 1));
}
/**
* Returns the nth geometry of a geometry collection, or the geometry if the input is not a
* collection.
*
* @param node xml element containing gml object(s)
* @param number integer number as the index of nth geometry
* @return geometry as a gml element
* @throws QueryException query exception
*/
@Deterministic
public ANode geometryN(final ANode node, final Int number) throws QueryException {
final Geometry geo = checkGeo(node);
final long n = number.itr();
if (n < 1 || n > geo.getNumGeometries()) throw GeoErrors.outOfRangeIdx(number);
return gmlWriter(geo.getGeometryN((int) n - 1));
}
/**
* Returns the number of interior rings in a polygon.
*
* @param node xml element containing gml object(s)
* @return integer number of interior rings
* @throws QueryException query exception
*/
@Deterministic
public Int numInteriorRing(final ANode node) throws QueryException {
final Geometry geo = geo(node, Q_GML_POLYGON);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Polygon");
return Int.get(((Polygon) geo).getNumInteriorRing());
}
/**
* Return a boolean value that shows weather the line is a ring or not. A line is a ring if it is
* closed and simple.
*
* @param node xml element containing gml object(s)
* @return boolean value
* @throws QueryException query exception
*/
@Deterministic
public Bln isRing(final ANode node) throws QueryException {
final Geometry geo = geo(node, Q_GML_LINEARRING, Q_GML_LINESTRING);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Line");
return Bln.get(((LineString) geo).isRing());
}
/**
* Returns the start point of a line.
*
* @param node xml element containing gml object(s)
* @return start point geometry as a gml element
* @throws QueryException query exception
*/
@Deterministic
public ANode startPoint(final ANode node) throws QueryException {
final Geometry geo = geo(node, Q_GML_LINEARRING, Q_GML_LINESTRING);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Line");
return gmlWriter(((LineString) geo).getStartPoint());
}
/**
* Returns the z-coordinate value for point.
*
* @param node xml element containing gml object(s)
* @return z double value
* @throws QueryException query exception
*/
@Deterministic
public Dbl z(final ANode node) throws QueryException {
final Geometry geo = geo(node, Q_GML_POINT);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Line");
return Dbl.get(geo.getCoordinate().z);
}
/**
* Checks if the line is closed loop. That is, if the start Point is same with end Point.
*
* @param node xml element containing gml object(s)
* @return boolean value
* @throws QueryException query exception
*/
@Deterministic
public Bln isClosed(final ANode node) throws QueryException {
final Geometry geo = geo(node, Q_GML_LINEARRING, Q_GML_LINESTRING, Q_GML_MULTILINESTRING);
if (geo == null && checkGeo(node) != null)
throw GeoErrors.geoType(node.qname().local(), "Line");
return Bln.get(
geo instanceof LineString
? ((LineString) geo).isClosed()
: ((MultiLineString) geo).isClosed());
}
/**
* Reads an element as a gml node. Returns a geometry element or {@code null} if the element does
* not match one of the specified types.
*
* @param node xml node containing gml object(s)
* @param names allowed geometry types
* @return geometry, or {@code null}
* @throws QueryException query exception
*/
private static Geometry geo(final ANode node, final QNm... names) throws QueryException {
if (node.type != NodeType.ELM) throw EXPTYPE_X_X_X.get(null, NodeType.ELM, node.type, node);
final QNm qname = node.qname();
for (final QNm geo : names) {
if (!qname.eq(geo)) continue;
// type found... create reader and geometry element
try {
final String input = node.serialize().toString();
final GMLReader gmlReader = new GMLReader();
final GeometryFactory geoFactory = new GeometryFactory();
return gmlReader.read(input, geoFactory);
} catch (final Throwable ex) {
throw GeoErrors.gmlReaderErr(ex);
}
}
return null;
}
/**
* Writes an geometry and returns a string representation of the geometry.
*
* @param geometry geometry
* @return DBNode database node
* @throws QueryException exception
*/
private DBNode gmlWriter(final Geometry geometry) throws QueryException {
final String geo;
try {
// write geometry and add namespace declaration
geo =
new GMLWriter()
.write(geometry)
.replaceAll("^<gml:(.*?)>", "<gml:$1 xmlns:gml='" + string(URI) + "'>");
} catch (final Exception ex) {
throw GeoErrors.gmlWriterErr(ex);
}
try {
final IO io = new IOContent(geo);
return new DBNode(MemBuilder.build(new XMLParser(io, queryContext.context.options)));
} catch (final IOException ex) {
throw IOERR_X.get(null, ex);
}
}
/**
* Reads an element as a gml node. Returns a geometry element or throws an exception if the
* element is of the wrong type.
*
* @param node xml node containing gml object(s)
* @return geometry
* @throws QueryException query exception
*/
private Geometry checkGeo(final ANode node) throws QueryException {
final Geometry geo = geo(node, QNAMES);
if (geo == null) throw GeoErrors.unrecognizedGeo(node.qname().local());
return geo;
}
