CircleHandler.java

/*
 * Copyright (c) 2016 wetransform GmbH
 * 
 * All rights reserved. This program and the accompanying materials are made
 * available under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the License,
 * or (at your option) any later version.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution. If not, see <http://www.gnu.org/licenses/>.
 * 
 * Contributors:
 *     wetransform GmbH <http://www.wetransform.to>
 */

package eu.esdihumboldt.hale.io.gml.geometry.handler;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import javax.xml.namespace.QName;

import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.LineString;

import de.fhg.igd.slf4jplus.ALogger;
import de.fhg.igd.slf4jplus.ALoggerFactory;
import eu.esdihumboldt.hale.common.core.io.IOProvider;
import eu.esdihumboldt.hale.common.instance.geometry.DefaultGeometryProperty;
import eu.esdihumboldt.hale.common.instance.geometry.InterpolationHelper;
import eu.esdihumboldt.hale.common.instance.model.Instance;
import eu.esdihumboldt.hale.common.schema.geometry.GeometryProperty;
import eu.esdihumboldt.hale.common.schema.model.TypeConstraint;
import eu.esdihumboldt.hale.common.schema.model.constraint.type.Binding;
import eu.esdihumboldt.hale.common.schema.model.constraint.type.GeometryType;
import eu.esdihumboldt.hale.io.gml.geometry.GeometryNotSupportedException;
import eu.esdihumboldt.hale.io.gml.geometry.constraint.GeometryFactory;
import eu.esdihumboldt.util.geometry.interpolation.InterpolationAlgorithm;
import eu.esdihumboldt.util.geometry.interpolation.model.Arc;
import eu.esdihumboldt.util.geometry.interpolation.model.ArcByCenterPoint;
import eu.esdihumboldt.util.geometry.interpolation.model.impl.ArcByCenterPointImpl;
import eu.esdihumboldt.util.geometry.interpolation.model.impl.ArcByPointsImpl;

/**
 * Handler for Circle geometries.
 * 
 * @author Arun Verma
 * @author Simon Templer
 */
public class CircleHandler extends LineStringHandler {

	private static final String CIRCLE_TYPE = "CircleType";

	private static final ALogger log = ALoggerFactory.getLogger(CircleHandler.class);

	@Override
	protected Set<? extends QName> initSupportedTypes() {
		Set<QName> types = new HashSet<QName>();

		types.add(new QName(NS_GML, CIRCLE_TYPE));
		types.add(new QName(NS_GML_32, CIRCLE_TYPE));

		return types;
	}

	@Override
	public Object createGeometry(Instance instance, int srsDimension, IOProvider reader)
			throws GeometryNotSupportedException {
		@SuppressWarnings("unchecked")
		DefaultGeometryProperty<LineString> lineStringGeomProperty = (DefaultGeometryProperty<LineString>) super.createGeometry(
				instance, srsDimension, reader);

		// create Arc for circle
		Coordinate[] coords = lineStringGeomProperty.getGeometry().getCoordinates();
		if (coords.length != 3) {
			throw new GeometryNotSupportedException("Arc must be defined by three points");
		}
		Arc arc = new ArcByPointsImpl(coords[0], coords[1], coords[2]);
		ArcByCenterPoint byCenter = arc.toArcByCenterPoint();

		ArcByCenterPoint circle = new ArcByCenterPointImpl(byCenter.getCenterPoint(),
				byCenter.getRadius(), byCenter.getStartAngle(), byCenter.getStartAngle(),
				byCenter.isClockwise());

		// get interpolation algorithm
		InterpolationAlgorithm interpol = InterpolationHelper.getInterpolation(reader,
				getGeometryFactory());
		LineString interpolatedCircle = interpol.interpolateArc(circle);

		if (interpolatedCircle == null) {
			log.error("Circle could be not interpolated to Linestring");
			return null;
		}
		return new DefaultGeometryProperty<LineString>(lineStringGeomProperty.getCRSDefinition(),
				interpolatedCircle);
	}

	@Override
	protected Collection<? extends TypeConstraint> initConstraints() {
		Collection<TypeConstraint> constraints = new ArrayList<TypeConstraint>(2);

		constraints.add(Binding.get(GeometryProperty.class));
		constraints.add(GeometryType.get(LineString.class));

		constraints.add(new GeometryFactory(this));

		return constraints;
	}

	@Override
	protected boolean isInterpolated() {
		return true;
	}
}