/* uDig - User Friendly Desktop Internet GIS client
* http://udig.refractions.net
* (C) 2011, Refractions Research Inc.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* (http://www.eclipse.org/legal/epl-v10.html), and the Refractions BSD
* License v1.0 (http://udig.refractions.net/files/bsd3-v10.html).
*/
package org.locationtech.udig.project.internal.property;
import java.net.URL;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.atomic.AtomicBoolean;
import org.locationtech.udig.catalog.CatalogPlugin;
import org.locationtech.udig.catalog.IGeoResource;
import org.locationtech.udig.catalog.objectproperty.ObjectPropertyCatalogListener;
import org.locationtech.udig.project.BlackboardEvent;
import org.locationtech.udig.project.IBlackboard;
import org.locationtech.udig.project.IBlackboardListener;
import org.locationtech.udig.project.ILayer;
import org.locationtech.udig.project.ProjectBlackboardConstants;
import org.locationtech.udig.ui.operations.AbstractPropertyValue;
import org.locationtech.udig.ui.operations.PropertyValue;
import org.geotools.data.FeatureSource;
/**
* Returns true if the layer has a FeatureSource as a resource.
*
* @author Jody Garnett (LISAsoft)
* @since 1.3.0
*/
public class FeatureSourceResourceProperty extends AbstractPropertyValue<ILayer>
implements PropertyValue<ILayer> {
private volatile AtomicBoolean isEvaluating = new AtomicBoolean(false);
private Set<URL> ids = new CopyOnWriteArraySet<URL>();
public boolean canCacheResult() {
return false;
}
public boolean isBlocking() {
return false;
}
public boolean isTrue( final ILayer object, String value ) {
isEvaluating.set(true);
try {
object.getBlackboard().addListener(new IBlackboardListener(){
public void blackBoardChanged( BlackboardEvent event ) {
if (event.getKey().equals(ProjectBlackboardConstants.LAYER__DATA_QUERY)) {
notifyListeners(object);
}
}
public void blackBoardCleared( IBlackboard source ) {
notifyListeners(object);
}
});
final IGeoResource resource = object.findGeoResource(FeatureSource.class);
if (resource != null && ids.add(resource.getIdentifier())) {
CatalogPlugin.getDefault().getLocalCatalog().addCatalogListener(
new ObjectPropertyCatalogListener(object, resource, isEvaluating, this));
}
boolean canResolve = resource.canResolve(FeatureSource.class);
return canResolve;
} catch (Exception e) {
return false;
} finally {
isEvaluating.set(false);
}
}
}