Application: gvSIG desktop

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import org.gvsig.fmap.dal.feature.FeatureAttributeDescriptor;

import org.gvsig.fmap.dal.feature.FeatureReference;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.geocoding.geommatches.MatcherUtils;

import org.gvsig.geocoding.result.DissolveResult;

	public List<DissolveResult> dissolveFeatures(

			FeatureAttributeDescriptor field, List<Feature> features) {

		List<DissolveResult> listResults = new ArrayList<DissolveResult>(); 

		// Group geometries by main attribute

		HashMap<String, List<Feature>> dissolAttributes = MatcherUtils

				.groupFeaturesByAttribute(field, features);

		// For each group of features, to do geometries dissolve process getting one o

		// more geometries

		for (Iterator<Map.Entry<String, List<Feature>>> iterator = dissolAttributes

				.entrySet().iterator(); iterator.hasNext();) {

			Map.Entry<String, List<Feature>> e = iterator.next();

			List<Feature> feats = e.getValue();

			// parse gvSIG geometries to JTS geometries

			List<Geometry> geoss = new ArrayList<Geometry>();

			for (int i = 0; i < feats.size(); i++) {

				geoss.add(feats.get(i).getDefaultGeometry());

			}

			List<com.vividsolutions.jts.geom.Geometry> jtsGeomsList = MatcherUtils

					.parseGeomsGVToJTS(geoss);

			// dissolve Lines (first geometry of array is Line)

			List<com.vividsolutions.jts.geom.Geometry> geomsDissol = null;

			if (jtsGeomsList.get(0).getDimension() == 1) {

				geomsDissol = MatcherUtils.dissolveLinesJTS(jtsGeomsList);

			}

			// dissolve Polys (first geometry of array is Poly)

			if (jtsGeomsList.get(0).getDimension() == 2) {

				geomsDissol = MatcherUtils.dissolvePolysJTS(jtsGeomsList);

			}

			// Parse JTS geometries to gvSIG geometries

			List<Geometry> gvGeoms = MatcherUtils

					.parseGeomsJTSToGV(geomsDissol);

			// Store dissolve geometries and the features references in the dissolve result

			DissolveResult res = new DissolveResult();

			res.setGeoms(gvGeoms);

			List <FeatureReference> refs = new ArrayList<FeatureReference>();

			for (int i = 0; i < feats.size(); i++) {

				refs.add(feats.get(i).getReference());

			}

			res.setFeaturesReferences(refs);

			listResults.add(res);

		}

		return listResults;

	}