Validation of a geometry in WKT format

Question

I am new to GIS area and I need to validate a geometry in WKT format in java, to check whether a simple polygon is a closed loop, i.e the start and end points of the vertices should be the same. I am currently using jGeometry class of oracle spatial(com.oracle.sdoapi), get the first and last vertices and comparing them. also, i am using getType() method to check whether it is a simple polygon or not. The following is the piece of code that am using:

WKT wkt = new WKT();
JGeometry geometry = wkt.toJGeometry(wkt.getBytes());
double[] d1 = geometry.getFirstPoint();
double[] d2 = geometry.getLastPoint();
if(!jGeometry.getType() == jGeometry.GTYPE_POLYGON){
 //error message for other geometries
}

Is there any simple way of doing this or is there any API available? I dont want to reinvent the wheel, if it is already done and simple to use. Thanks!

Answer 1

The Java Topology Suite contains a WKTReader class that will suit your purposes. See http://tsusiatsoftware.net/jts/javadoc/com/vividsolutions/jts/io/WKTReader.html. You can use WKTReader to parse the WKT, and look for ParseExceptions, which indicate an invalid WKT.

If the WKT parses, you can then use the instanceof operator or WKTReader.getGeometryType() to determine the type of parsed Geometry class, and see if it's one of the Geometry types (Polygon or Multipolygon) with closed shells like Polygon or Multipolygon.