/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2011, Open Source Geospatial Foundation (OSGeo)
* (C) 2001-2007 TOPP - www.openplans.org.
*
* 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.vector;
import java.util.logging.Logger;
import org.geotools.feature.DefaultFeatureCollection;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.feature.simple.SimpleFeatureBuilder;
import org.geotools.process.ProcessException;
import org.geotools.process.factory.DescribeParameter;
import org.geotools.process.factory.DescribeProcess;
import org.geotools.process.factory.DescribeResult;
import org.geotools.util.logging.Logging;
import org.opengis.feature.Feature;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.feature.type.AttributeDescriptor;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryFactory;
import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.geom.MultiLineString;
import com.vividsolutions.jts.linearref.LengthIndexedLine;
import com.vividsolutions.jts.operation.linemerge.LineMerger;
@DescribeProcess(title = "Extract Segment in LRS", description = "Extracts segment between a given start and end measure from LRS features")
/**
*
*
* @source $URL: http://svn.osgeo.org/geotools/trunk/modules/unsupported/process-feature/src/main/java/org/geotools/process/feature/gs/NearestProcess.java $
*/
public class LRSSegmentProcess implements VectorProcess {
private static final Logger LOGGER = Logging.getLogger(LRSSegmentProcess.class);
private final GeometryFactory geometryFactory = new GeometryFactory();
/**
* Process the input data set.
*
* @param featureCollection the data set
* @param crs the CRS
* @param point the given point
* @return the snapped to feature
* @throws ProcessException error
*/
@DescribeResult(name = "result", description = "Output feature collection")
public FeatureCollection execute(
@DescribeParameter(name = "features", description = "Input feature collection") FeatureCollection featureCollection,
@DescribeParameter(name = "from_measure_attb", description = "Attribute providing start measure of feature") String fromMeasureAttb,
@DescribeParameter(name = "to_measure_attb", description = "Attribute providing end measure of feature") String toMeasureAttb,
@DescribeParameter(name = "from_measure", description = "Measure for start of segment to extract") Double fromMeasure,
@DescribeParameter(name = "to_measure", description = "Measure for end of segment to extract") Double toMeasure)
throws ProcessException {
DefaultFeatureCollection results = new DefaultFeatureCollection();
try {
if (featureCollection == null || featureCollection.size() == 0) {
LOGGER.info("No features provided in request");
return results;
}
if (fromMeasureAttb == null
|| featureCollection.getSchema().getDescriptor(fromMeasureAttb) == null) {
throw new ProcessException(
"The from_measure_attb parameter was not provided or not defined in schema");
}
if (toMeasureAttb == null
|| featureCollection.getSchema().getDescriptor(toMeasureAttb) == null) {
throw new ProcessException("The to_measure_attb parameter was not provided");
}
if (fromMeasure == null) {
throw new ProcessException("The from_measure parameter was not provided");
}
if (toMeasure == null) {
throw new ProcessException("The to_measure parameter was not provided");
}
if (fromMeasure.doubleValue() == toMeasure.doubleValue()) {
LOGGER.info("Zero length segment requested");
return results;
}
FeatureIterator<Feature> featureIterator = null;
Feature firstFeature = null;
try {
LineMerger lineMerger = new LineMerger();
if (toMeasure.doubleValue() > fromMeasure.doubleValue()) {
featureIterator = featureCollection.features();
while (featureIterator.hasNext()) {
Feature feature = featureIterator.next();
if (firstFeature == null)
firstFeature = feature;
Double featureFromMeasure = (Double) feature.getProperty(fromMeasureAttb)
.getValue();
Double featureToMeasure = (Double) feature.getProperty(toMeasureAttb)
.getValue();
if (fromMeasure < featureToMeasure && toMeasure > featureFromMeasure) {
try {
if (fromMeasure <= featureFromMeasure
&& toMeasure >= featureToMeasure) {
lineMerger.add((Geometry) feature.getDefaultGeometryProperty()
.getValue());
} else if (fromMeasure > featureFromMeasure
&& toMeasure < featureToMeasure) {
LengthIndexedLine lengthIndexedLine = new LengthIndexedLine(
(Geometry) feature.getDefaultGeometryProperty()
.getValue());
double featureLength = featureToMeasure - featureFromMeasure;
double startOffset = fromMeasure - featureFromMeasure;
double stopOffset = toMeasure - featureFromMeasure;
double calcLength = ((Geometry) feature
.getDefaultGeometryProperty().getValue()).getLength();
if (calcLength == 0 || featureLength == 0)
continue;
Geometry extracted = lengthIndexedLine.extractLine(startOffset
* calcLength / featureLength, stopOffset * calcLength
/ featureLength);
if (!extracted.isEmpty())
lineMerger.add(extracted);
} else if (fromMeasure > featureFromMeasure) {
LengthIndexedLine lengthIndexedLine = new LengthIndexedLine(
(Geometry) feature.getDefaultGeometryProperty()
.getValue());
double featureLength = featureToMeasure - featureFromMeasure;
double startOffset = fromMeasure - featureFromMeasure;
double calcLength = ((Geometry) feature
.getDefaultGeometryProperty().getValue()).getLength();
if (calcLength == 0 || featureLength == 0)
continue;
Geometry extracted = lengthIndexedLine.extractLine(startOffset
* calcLength / featureLength, calcLength);
if (!extracted.isEmpty())
lineMerger.add(extracted);
} else {
LengthIndexedLine lengthIndexedLine = new LengthIndexedLine(
(Geometry) feature.getDefaultGeometryProperty()
.getValue());
double featureLength = featureToMeasure - featureFromMeasure;
double stopOffset = toMeasure - featureFromMeasure;
double calcLength = ((Geometry) feature
.getDefaultGeometryProperty().getValue()).getLength();
if (calcLength == 0 || featureLength == 0)
continue;
Geometry extracted = lengthIndexedLine.extractLine(0,
stopOffset * calcLength / featureLength);
if (extracted.isEmpty() || extracted.getLength() == 0.0) {
LOGGER.info("Empty segment: featureFromMeasure="
+ featureFromMeasure + " featureToMeasure:"
+ featureToMeasure + " toMeasure:" + toMeasure
+ " fromMeasure:" + fromMeasure);
} else {
lineMerger.add(extracted);
}
}
} catch (Exception e) {
LOGGER.warning("Error merging line strings: " + e
+ " featureFromMeasure=" + featureFromMeasure
+ " featureToMeasure:" + featureToMeasure + " toMeasure:"
+ toMeasure + " fromMeasure:" + fromMeasure);
}
}
}
results.add(createTargetFeature(firstFeature, (SimpleFeatureType) firstFeature
.getType(), new MultiLineString((LineString[]) lineMerger
.getMergedLineStrings().toArray(new LineString[0]), geometryFactory)));
}
} finally {
if (featureIterator != null)
featureIterator.close();
}
return results;
} catch (ProcessException e) {
throw e;
} catch (Throwable e) {
LOGGER.warning("Error executing method: " + e);
throw new ProcessException("Error executing method: " + e, e);
}
}
/**
* Create the modified feature.
*
* @param feature the source feature
* @param targetFeatureType the modified feature type
* @param nearestDistance the snap distance
* @param nearestBearing the snap bearing
* @return the modified feature
* @throws ProcessException error
*/
private SimpleFeature createTargetFeature(Feature feature, SimpleFeatureType targetFeatureType,
MultiLineString multiLineString) throws ProcessException {
try {
AttributeDescriptor geomAttbType = targetFeatureType.getGeometryDescriptor();
Object[] attributes = new Object[targetFeatureType.getAttributeCount()];
for (int i = 0; i < attributes.length; i++) {
AttributeDescriptor attbType = targetFeatureType.getAttributeDescriptors().get(i);
if (attbType.equals(geomAttbType)) {
attributes[i] = multiLineString;
} else {
attributes[i] = feature.getProperty(attbType.getName()).getValue();
}
}
return SimpleFeatureBuilder.build(targetFeatureType, attributes, feature
.getIdentifier().getID());
} catch (Exception e) {
LOGGER.warning("Error creating feature: " + e);
throw new ProcessException("Error creating feature: " + e, e);
}
}
}