/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2014, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
package org.geotools.process.spatialstatistics.operations;
import java.io.IOException;
import java.util.Hashtable;
import java.util.logging.Logger;
import org.geotools.data.simple.SimpleFeatureCollection;
import org.geotools.data.simple.SimpleFeatureIterator;
import org.geotools.process.spatialstatistics.core.FeatureTypes;
import org.geotools.process.spatialstatistics.storage.IFeatureInserter;
import org.geotools.util.logging.Logging;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.filter.Filter;
import org.opengis.filter.expression.Expression;
import org.opengis.filter.sort.SortBy;
import org.opengis.filter.sort.SortOrder;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
import com.vividsolutions.jts.geom.CoordinateList;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.geom.Polygon;
/**
* Creates line features from points.
*
* @author Minpa Lee, MangoSystem
*
* @source $URL$
*/
public class PointsToLineOperation extends GeneralOperation {
protected static final Logger LOGGER = Logging.getLogger(PointsToLineOperation.class);
private static final String length = "length";
private boolean closeLine = false;
private String lineField = null;
public SimpleFeatureCollection execute(SimpleFeatureCollection inputFeatures, String lineField,
String sortField, boolean closeLine) throws IOException {
this.closeLine = closeLine;
// prepare feature type
SimpleFeatureType inputSchema = inputFeatures.getSchema();
String typeName = inputSchema.getTypeName();
CoordinateReferenceSystem crs = inputSchema.getCoordinateReferenceSystem();
String geomName = inputFeatures.getSchema().getGeometryDescriptor().getLocalName();
SimpleFeatureType featureType = FeatureTypes.getDefaultType(typeName, geomName,
LineString.class, crs);
if (closeLine) {
featureType = FeatureTypes.getDefaultType(typeName, geomName, Polygon.class, crs);
}
boolean hasLineField = lineField != null && lineField.length() > 0;
boolean hasSortField = sortField != null && sortField.length() > 0;
if (hasLineField) {
lineField = FeatureTypes.validateProperty(inputSchema, lineField);
hasLineField = inputSchema.indexOf(lineField) != -1;
if (hasLineField) {
featureType = FeatureTypes.add(featureType, inputSchema.getDescriptor(lineField));
this.lineField = lineField;
}
}
featureType = FeatureTypes.add(featureType, length, Double.class, 33);
if (hasSortField) {
sortField = FeatureTypes.validateProperty(inputSchema, sortField);
hasSortField = inputSchema.indexOf(sortField) != -1;
}
// prepare transactional feature store
IFeatureInserter featureWriter = getFeatureWriter(featureType);
try {
SimpleFeatureCollection subCollection = inputFeatures;
if (hasLineField) {
Hashtable<Object, Object> uvValues = getUniqueValues(inputFeatures, lineField);
for (Object uvValue : uvValues.keySet()) {
Filter filter = ff.equal(ff.property(lineField), ff.literal(uvValue), true);
subCollection = inputFeatures.subCollection(filter);
if (hasSortField) {
SortBy sort = ff.sort(sortField, SortOrder.ASCENDING);
insertFeatures(subCollection.sort(sort), uvValue, featureWriter);
} else {
insertFeatures(subCollection, uvValue, featureWriter);
}
}
} else {
if (hasSortField) {
subCollection = inputFeatures.sort(ff.sort(sortField, SortOrder.ASCENDING));
}
insertFeatures(subCollection, null, featureWriter);
}
} catch (Exception e) {
featureWriter.rollback(e);
} finally {
featureWriter.close(null);
}
return featureWriter.getFeatureCollection();
}
private void insertFeatures(SimpleFeatureCollection inputFeatures, Object lineValue,
IFeatureInserter featureWriter) throws IOException {
CoordinateList coordinates = new CoordinateList();
SimpleFeatureIterator featureIter = inputFeatures.features();
try {
while (featureIter.hasNext()) {
SimpleFeature feature = featureIter.next();
Geometry geometry = (Geometry) feature.getDefaultGeometry();
if (geometry == null || geometry.isEmpty()) {
continue;
}
coordinates.add(geometry.getCoordinate(), false);
}
} finally {
featureIter.close();
}
if (coordinates.size() <= 1) {
return;
}
if (coordinates.size() > 1) {
// create feature and set geometry
Geometry geometry = null;
if (closeLine) {
coordinates.add(coordinates.get(0), false);
geometry = gf.createPolygon(coordinates.toCoordinateArray());
} else {
geometry = gf.createLineString(coordinates.toCoordinateArray());
}
if (geometry == null || geometry.isEmpty()) {
return;
}
SimpleFeature newFeature = featureWriter.buildFeature();
newFeature.setDefaultGeometry(geometry);
if (lineValue != null && lineField != null) {
newFeature.setAttribute(lineField, lineValue);
}
newFeature.setAttribute(length, geometry.getLength());
featureWriter.write(newFeature);
}
}
private Hashtable<Object, Object> getUniqueValues(SimpleFeatureCollection inputFeatures,
String lineField) {
Hashtable<Object, Object> table = new Hashtable<Object, Object>();
SimpleFeatureIterator featureIter = inputFeatures.features();
try {
Expression expression = ff.property(lineField);
while (featureIter.hasNext()) {
Object value = expression.evaluate(featureIter.next());
if (value == null) {
// skip null value feature
continue;
}
table.put(value, value);
}
} finally {
featureIter.close();
}
return table;
}
}