presto-geospatial/src/main/java/io/prestosql/plugin/geospatial/GeoFunctions.java/GeoFunctions/stIsClosed
class GeoFunctions:    @SqlNullable
    @Description("Returns TRUE if the LineString or Multi-LineString's start and end points are coincident")
    @ScalarFunction("ST_IsClosed")
    @SqlType(BOOLEAN)
    public static Boolean stIsClosed(@SqlType(GEOMETRY_TYPE_NAME) Slice input)
    {
        OGCGeometry geometry = deserialize(input);
        validateType("ST_IsClosed", geometry, EnumSet.of(LINE_STRING, MULTI_LINE_STRING));
        MultiPath lines = (MultiPath) geometry.getEsriGeometry();
        int pathCount = lines.getPathCount();
        for (int i = 0; i < pathCount; i++) {
            Point start = lines.getPoint(lines.getPathStart(i));
            Point end = lines.getPoint(lines.getPathEnd(i) - 1);
            if (!end.equals(start)) {
                return false;
            }
        }
        return true;
    }