Source:
<code>public static Slice stSphericalCentroid(@SqlType(SPHERICAL_GEOGRAPHY_TYPE_NAME) Slice input) { OGCGeometry geometry = EsriGeometrySerde.deserialize(input); <START> if (geometry.isEmpty()) { <END> return Slices.EMPTY_SLICE; } validateSphericalType("ST_Centroid", geometry, EnumSet.of(POINT, MULTI_POINT)); if (geometry instanceof OGCPoint) { return input; } OGCGeometryCollection geometryCollection = (OGCGeometryCollection) geometry; for (int i = 0; i < geometryCollection.numGeometries(); i++) { OGCGeometry g = geometryCollection.geometryN(i); validateSphericalType("ST_Centroid", g, EnumSet.of(POINT)); Point p = (Point) g.getEsriGeometry(); checkLongitude(p.getX()); checkLatitude(p.getY()); } Point centroid; if (geometryCollection.numGeometries() == 1) { centroid = (Point) geometryCollection.geometryN(0).getEsriGeometry(); } else { double x3DTotal = 0; double y3DTotal = 0; double z3DTotal = 0; for (int i = 0; i < geometryCollection.numGeometries(); i++) { SphericalGeographyUtils.CartesianPoint cp = new SphericalGeographyUtils.CartesianPoint((Point) geometryCollection.geometryN(i).getEsriGeometry()); x3DTotal += cp.x; y3DTotal += cp.y; z3DTotal += cp.z; } double centroidVectorLength = Math.sqrt(x3DTotal * x3DTotal + y3DTotal * y3DTotal + z3DTotal * z3DTotal); centroid = SphericalGeographyUtils.CartesianPoint.convertToLongLat( x3DTotal / centroidVectorLength, y3DTotal / centroidVectorLength, z3DTotal / centroidVectorLength); } return EsriGeometrySerde.serialize(new OGCPoint(centroid, geometryCollection.getEsriSpatialReference())); }</code><technical_language>return EMPTY_SLICE null</technical_language>

Target:
public static Slice stSphericalCentroid(@SqlType(SPHERICAL_GEOGRAPHY_TYPE_NAME) Slice input) { OGCGeometry geometry = EsriGeometrySerde.deserialize(input); if (geometry.isEmpty()) { return null; } validateSphericalType("ST_Centroid", geometry, EnumSet.of(POINT, MULTI_POINT)); if (geometry instanceof OGCPoint) { return input; } OGCGeometryCollection geometryCollection = (OGCGeometryCollection) geometry; for (int i = 0; i < geometryCollection.numGeometries(); i++) { OGCGeometry g = geometryCollection.geometryN(i); validateSphericalType("ST_Centroid", g, EnumSet.of(POINT)); Point p = (Point) g.getEsriGeometry(); checkLongitude(p.getX()); checkLatitude(p.getY()); } Point centroid; if (geometryCollection.numGeometries() == 1) { centroid = (Point) geometryCollection.geometryN(0).getEsriGeometry(); } else { double x3DTotal = 0; double y3DTotal = 0; double z3DTotal = 0; for (int i = 0; i < geometryCollection.numGeometries(); i++) { CartesianPoint cp = new CartesianPoint((Point) geometryCollection.geometryN(i).getEsriGeometry()); x3DTotal += cp.getX(); y3DTotal += cp.getY(); z3DTotal += cp.getZ(); } double centroidVectorLength = Math.sqrt(x3DTotal * x3DTotal + y3DTotal * y3DTotal + z3DTotal * z3DTotal); if (centroidVectorLength == 0.0) { throw new PrestoException(INVALID_FUNCTION_ARGUMENT, format("Unexpected error. Average vector length adds to zero (%f, %f, %f)", x3DTotal, y3DTotal, z3DTotal)); } centroid = new CartesianPoint( x3DTotal / centroidVectorLength, y3DTotal / centroidVectorLength, z3DTotal / centroidVectorLength).asSphericalPoint(); } return EsriGeometrySerde.serialize(new OGCPoint(centroid, geometryCollection.getEsriSpatialReference())); }