/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2008, 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.feature;
import java.util.HashMap;
import java.util.Map;
import org.geotools.feature.DefaultFeatureCollection;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.feature.simple.SimpleFeatureBuilder;
import org.geotools.util.NullProgressListener;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.util.ProgressListener;
/**
* Abstract implementation of Process for feature collections.
* <p>
* Subclasses need to implement {@link #processFeature(SimpleFeature, Map)}. This method
* should perform the operation on the feature, changing any attributes on the feature
* as necessary.
* </p>
*
* @see FeatureToFeatureProcessFactory
* @author Justin Deoliveira, OpenGEO
*
* @since 2.6
*
*
*
*
* @source $URL$
*/
public abstract class FeatureToFeatureProcess extends AbstractFeatureCollectionProcess {
/**
* Constructor
*
* @param factory
*/
public FeatureToFeatureProcess(FeatureToFeatureProcessFactory factory) {
super(factory);
}
public final Map<String, Object> execute(Map<String, Object> input,
ProgressListener monitor) {
if ( monitor == null ) {
monitor = new NullProgressListener();
}
//read the parameters, features and buffer amount
FeatureCollection features =
(FeatureCollection) input.get( FeatureToFeatureProcessFactory.FEATURES.key );
//start progress
float scale = 100f / features.size();
monitor.started();
//create the result feature collection
SimpleFeatureType targetSchema = getTargetSchema((SimpleFeatureType) features.getSchema(), input);
DefaultFeatureCollection result = new DefaultFeatureCollection(null, targetSchema);
SimpleFeatureBuilder fb = new SimpleFeatureBuilder((SimpleFeatureType) result.getSchema());
FeatureIterator fi = features.features();
try {
int counter = 0;
while( fi.hasNext() ) {
//copy the feature
fb.init((SimpleFeature) fi.next());
SimpleFeature feature = fb.buildFeature(null);
//buffer the geometry
try {
processFeature( feature, input );
}
catch( Exception e ) {
monitor.exceptionOccurred( e );
}
monitor.progress( scale * counter++);
result.add( feature );
}
}
finally {
fi.close();
}
monitor.complete();
//return the result
Map<String,Object> output = new HashMap<String, Object>();
output.put( FeatureToFeatureProcessFactory.RESULT.key, result );
return output;
}
/**
* Subclasses should override if the target schema is different that then original schema
* (mind, if the number of attributes changes it's better to roll your own class instead
* of using this one)
* @param sourceSchema
* @param input
* @return
*/
protected SimpleFeatureType getTargetSchema(SimpleFeatureType sourceSchema, Map<String, Object> input) {
return sourceSchema;
}
}