/* Copyright (c) 2001 - 2007 TOPP - www.openplans.org. All rights reserved.
* This code is licensed under the GPL 2.0 license, availible at the root
* application directory.
*/
package org.geoserver.wfs.response;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.feature.collection.DecoratingFeatureCollection;
import org.geotools.feature.collection.DelegateFeatureIterator;
import org.geotools.feature.simple.SimpleFeatureBuilder;
import org.geotools.feature.simple.SimpleFeatureTypeBuilder;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.feature.type.AttributeDescriptor;
import org.opengis.feature.type.GeometryDescriptor;
/**
* FeatureCollection that remaps attribute names using a given map.
*
* @author Mauro Bartolomeoli, mbarto@infosia.it
*
*/
public class RemappingFeatureCollection extends DecoratingFeatureCollection<SimpleFeatureType, SimpleFeature> {
Map<String,String> attributesMapping;
public RemappingFeatureCollection(FeatureCollection<SimpleFeatureType, SimpleFeature> delegate,Map<String,String> attributesMapping) {
super(delegate);
this.attributesMapping=attributesMapping;
}
public SimpleFeatureType getSchema() {
return remapSchema(delegate.getSchema());
}
/**
* Builds an inverted version of the given map.
* Inversion means that key->value becomes value->key
* @param map
* @return
*/
static Map<String,String> invertMappings(Map<String,String> map) {
Map<String,String> result=new HashMap<String,String>();
for(String key:map.keySet())
result.put(map.get(key),key);
return result;
}
/**
* Gets a new schema, built remapping attribute names via
* the attributeMappings map.
* @param schema
* @return
*/
private SimpleFeatureType remapSchema(SimpleFeatureType schema) {
SimpleFeatureTypeBuilder builder=new SimpleFeatureTypeBuilder();
builder.setName(schema.getName());
for(AttributeDescriptor attDesc : schema.getAttributeDescriptors()) {
if(attDesc instanceof GeometryDescriptor) {
GeometryDescriptor geoDesc=(GeometryDescriptor)attDesc;
builder.add(attributesMapping.get(attDesc.getLocalName()),attDesc.getType().getBinding(),geoDesc.getCoordinateReferenceSystem());
} else
builder.add(attributesMapping.get(attDesc.getLocalName()),attDesc.getType().getBinding());
}
return builder.buildFeatureType();
}
public Iterator<SimpleFeature> iterator() {
return new RemappingIterator(delegate.iterator(), attributesMapping,getSchema());
}
public void close(Iterator<SimpleFeature> iterator) {
RemappingIterator remapping = (RemappingIterator) iterator;
delegate.close(remapping.delegate);
}
public FeatureIterator<SimpleFeature> features() {
return new DelegateFeatureIterator<SimpleFeature>(this, iterator());
}
public void close(FeatureIterator<SimpleFeature> iterator) {
DelegateFeatureIterator<SimpleFeature> delegate = (DelegateFeatureIterator<SimpleFeature>) iterator;
delegate.close();
}
/**
* Remaps a SimpleFeature, using the given mappings (oldname -> mappedname).
* The builder uses the mapped schema.
*
* @param source
* @param attributeMappings
* @param builder
* @return
*/
static SimpleFeature remap(SimpleFeature source, Map<String,String> attributeMappings,SimpleFeatureBuilder builder) {
SimpleFeatureType target = builder.getFeatureType();
for (int i = 0; i < target.getAttributeCount(); i++) {
AttributeDescriptor attributeType = target.getDescriptor(i);
Object value = null;
String mappedName=attributeMappings.get(attributeType.getLocalName());
if (source.getFeatureType().getDescriptor(mappedName) != null) {
value = source.getAttribute(mappedName);
}
builder.add(value);
}
return builder.buildFeature(source.getIdentifier().getID());
}
public static class RemappingIterator implements Iterator<SimpleFeature> {
Map<String,String> attributesMapping;
Iterator<SimpleFeature> delegate;
SimpleFeatureBuilder builder;
public RemappingIterator(Iterator<SimpleFeature> delegate, Map attributesMapping,SimpleFeatureType schema) {
this.delegate = delegate;
this.attributesMapping = RemappingFeatureCollection.invertMappings(attributesMapping);
this.builder = new SimpleFeatureBuilder(schema);
}
public boolean hasNext() {
return delegate.hasNext();
}
public SimpleFeature next() {
return RemappingFeatureCollection.remap(delegate.next(), attributesMapping,builder);
}
public void remove() {
delegate.remove();
}
}
}