import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
public static ClobType geometryToGml(CommandContext ctx, GeometryType geometry, 
                                     boolean withGmlPrefix) 
        throws FunctionExecutionException {        
    Geometry jtsGeometry = getGeometry(geometry);
    GMLWriter writer = new GMLWriter();
    
    if (!withGmlPrefix) {
    	if (geometry.getSrid() != SRID_4326) {
    		if (geometry.getSrid() == GeometryType.UNKNOWN_SRID) {
    			throw new FunctionExecutionException(QueryPlugin.Util.gs(QueryPlugin.Event.TEIID31161));
    		}
    		jtsGeometry = GeometryTransformUtils.transform(ctx, jtsGeometry, SRID_4326);
    	}
        writer.setPrefix(null);
    } else if (geometry.getSrid() != GeometryType.UNKNOWN_SRID) {
    	//TODO: should include the srsName
    	//writer.setSrsName(String.valueOf(geometry.getSrid()));
    }
    String gmlText = writer.write(jtsGeometry);
    return new ClobType(new ClobImpl(gmlText));
}
 

import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
/**
 * JTS library conversion from geometry to GML.
 * @param geo base Geometry gets delegated
 * @return String gml encoding of the geomoetry
 */
private static String geoToGmlUseJtsLib(final Geometry geo) {
    final int srid = geo.getSRID();
    final GMLWriter gmlWriter = new GMLWriter();
    gmlWriter.setNamespace(false);
    gmlWriter.setPrefix(null);

    if (srid != -1 || srid != 0) {
        gmlWriter.setSrsName("EPSG:" + geo.getSRID());
    }
    final String gml = gmlWriter.write(geo);
    // Hack to replace a gml 2.0 deprecated element in the Polygon.
    // It should tolerate this as it does other depreciated elements like <gml:coordinates>.
    return gml.replace("outerBoundaryIs", "exterior");
}
 

import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
private JTSWrapper() {
  // use a private constructor to force call of getInstance method and forbid subclassing
  wktr = new WKTReader();
  wktw = new WKTWriter();
  wkbr = new WKBReader();
  wkbw = new WKBWriter(); // PostGIS
  // wkbw = new WKBWriter(2, WKBConstants.wkbXDR); // MonetDB
  gmlw = new GMLWriter();

  numDecimalPlaces = (new PrecisionModel()).getMaximumSignificantDigits();
}
 

import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
public static String asGml(ValueMetaInterface metaA, Object dataA) throws KettleValueException{
    if (dataA==null || !metaA.isGeometry()) 
    	return null;
    GMLWriter gmlWriter = new GMLWriter();
    if ((metaA.getGeometrySRS()!=null) && (metaA.getGeometrySRS().getSRID()!=-1))
    	gmlWriter.setSrsName("EPSG:"+metaA.getGeometrySRS().getSRID());
    gmlWriter.setPrefix("gml");
    return gmlWriter.write(metaA.getGeometry(dataA));        
}
 

import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
public static String asKml(ValueMetaInterface metaA, Object dataA) throws KettleValueException{
    if (dataA==null || !metaA.isGeometry()) 
    	return null;
    GMLWriter kmlWriter = new GMLWriter();
    kmlWriter.setPrefix("kml");
    return kmlWriter.write(metaA.getGeometry(dataA));        
}
 

import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
public static String toGML2(Geometry g)
{
  GMLWriter writer = new GMLWriter();
  return writer.write(g);
}
 

import com.vividsolutions.jts.io.gml2.GMLWriter; //导入依赖的package包/类
public static void main(String[] args) throws ParseException, NoSuchAuthorityCodeException, FactoryException, IOException, SchemaException, java.text.ParseException {
	
	   String wktGeometry = "POLYGON ((-61.6866679999999974 17.0244409999999995, -61.8872220000000013 17.1052740000000014, -61.7944490000000002 17.1633299999999984, -61.6866679999999974 17.0244409999999995)) POLYGON ((-61.7291719999999984 17.6086080000000003, -61.8530579999999972 17.5830540000000006, -61.8730619999999973 17.7038879999999992, -61.7291719999999984 17.6086080000000003))";
	   WKTReader wktR = new WKTReader();
	   
	   Geometry geom = wktR.read(wktGeometry);

	   // write JTS to string
	   GMLWriter gmlW = new GMLWriter(true);
	   gmlW.setSrsName("<http://www.opengis.net/def/crs/EPSG/0/4326>");
	   String gml = gmlW.write(geom);
	   
	   System.out.println(gml);
	   
	   GeometryBuilder gb = new GeometryBuilder(gml);
	   
	   WKTParser wktp = new WKTParser(gb);
	   wktp.parse(wktGeometry);
        
        
}