/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2009, 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.jdbc;
import org.geotools.data.FeatureStore;
import org.geotools.data.QueryCapabilities;
import org.opengis.feature.type.AttributeDescriptor;
import org.opengis.filter.expression.PropertyName;
import org.opengis.filter.sort.SortBy;
import org.opengis.filter.sort.SortOrder;
import com.vividsolutions.jts.geom.Geometry;
/**
* A default QueryCapabilities implementation for JDBCFeatureSource.
*
* @author Gabriel Roldan (TOPP)
* @author Andrea Aime (OpenGeo)
* @version $Id$
* @since 2.5.4
*/
class JDBCQueryCapabilities extends QueryCapabilities {
JDBCFeatureSource source;
public JDBCQueryCapabilities(JDBCFeatureSource source) {
this.source = source;
}
@Override
public boolean supportsSorting(final SortBy[] sortAttributes) {
if(super.supportsSorting(sortAttributes))
return true;
for (int i = 0; i < sortAttributes.length; i++) {
SortBy sortBy = sortAttributes[i];
if (SortBy.NATURAL_ORDER == sortBy || SortBy.REVERSE_ORDER == sortBy) {
// we do only if we have a non null primary key
return !(source.getPrimaryKey() instanceof NullPrimaryKey);
} else {
PropertyName propertyName = sortBy.getPropertyName();
SortOrder sortOrder = sortBy.getSortOrder();
if (!supportsPropertySorting(propertyName, sortOrder)) {
return false;
}
}
}
return true;
}
/**
* Checks for sorting support in the given sort order for a specific attribute type,
* given by a PropertyName expression.
* <p>
* This default implementation assumes both orders are supported as long as the property
* name corresponds to the name of one of the attribute types in the complete FeatureType,
* and that the attribute is not a geometry.
* </p>
*
* @param propertyName the expression holding the property name to check for sortability
* support
* @param sortOrder the order, ascending or descending, to check for sortability support
* over the given property name.
* @return true if propertyName refers to one of the FeatureType attributes
*/
protected boolean supportsPropertySorting(PropertyName propertyName, SortOrder sortOrder) {
AttributeDescriptor descriptor = (AttributeDescriptor) propertyName.evaluate(source.getSchema());
if(descriptor == null) {
String attName = propertyName.getPropertyName();
descriptor = source.getSchema().getDescriptor(attName);
}
return descriptor != null && !(Geometry.class.isAssignableFrom(descriptor.getType().getBinding()));
}
/**
* Consults the fid mapper for the feature source, if the null feature map reliable fids
* not supported.
*/
@Override
public boolean isReliableFIDSupported() {
return !(source.getPrimaryKey() instanceof NullPrimaryKey);
}
@Override
public boolean isOffsetSupported() {
return source.getDataStore().getSQLDialect().isLimitOffsetSupported();
}
@Override
public boolean isUseProvidedFIDSupported() {
return true;
}
}