/*
* Geotoolkit - An Open Source Java GIS Toolkit
* http://www.geotoolkit.org
*
* (C) 2002-2008, 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.geotoolkit.filter.visitor;
import java.util.logging.Logger;
import org.geotoolkit.geometry.jts.JTSEnvelope2D;
import org.opengis.filter.ExcludeFilter;
import org.opengis.filter.IncludeFilter;
import org.opengis.filter.expression.Literal;
import org.opengis.filter.spatial.BBOX;
import org.opengis.filter.spatial.Beyond;
import org.opengis.filter.spatial.Contains;
import org.opengis.filter.spatial.Crosses;
import org.opengis.filter.spatial.DWithin;
import org.opengis.filter.spatial.Disjoint;
import org.opengis.filter.spatial.Equals;
import org.opengis.filter.spatial.Intersects;
import org.opengis.filter.spatial.Overlaps;
import org.opengis.filter.spatial.Touches;
import org.opengis.filter.spatial.Within;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
import com.vividsolutions.jts.geom.Envelope;
import com.vividsolutions.jts.geom.Geometry;
import org.apache.sis.util.logging.Logging;
/**
* Extract a maximal envelope from the provided Filter.
* <p>
* The maximal envelope is generated from:
* <ul>
* <li>all the literal geometry instances involved if spatial operations - using
* geom.getEnvelopeInternal().
* <li>Filter.EXCLUDES will result in <code>null</code>
* <li>Filter.INCLUDES will result in a "world" envelope with range Double.NEGATIVE_INFINITY to
* Double.POSITIVE_INFINITY for each axis.
* </ul>
* Since geometry literals do not contains CRS information we can only produce a ReferencedEnvelope
* without CRS information. You can call this function with an existing ReferencedEnvelope
* or with your data CRS to correct for this limitation.
* ReferencedEnvelope example:<pre><code>
* ReferencedEnvelope bbox = (ReferencedEnvelope)
* filter.accepts(new ExtractBoundsFilterVisitor(), dataCRS );
* </code></pre>
* You can also call this function with an existing Envelope; if you are building up bounds based on
* several filters.
* <p>
* This is a replacement for FilterConsumer.
*
* @author Jody Garnett
* @module
*/
public class ExtractBoundsFilterVisitor extends NullFilterVisitor {
static public NullFilterVisitor BOUNDS_VISITOR = new ExtractBoundsFilterVisitor();
private static final Logger LOGGER = Logging.getLogger("org.geotoolkit.filter.visitor");
/**
* This FilterVisitor is stateless - use ExtractBoundsFilterVisitor.BOUNDS_VISITOR.
* <p>
* You may also subclass in order to reuse this functionality in your own
* FilterVisitor implementation.
*/
protected ExtractBoundsFilterVisitor(){
}
/**
* Produce an ReferencedEnvelope from the provided data parameter.
*
* @param data
* @return ReferencedEnvelope
*/
private JTSEnvelope2D bbox( final Object data ) {
if( data == null ){
return null;
}
else if (data instanceof JTSEnvelope2D) {
return (JTSEnvelope2D) data;
}
else if (data instanceof Envelope){
return new JTSEnvelope2D( (Envelope) data, null );
}
else if (data instanceof CoordinateReferenceSystem){
return new JTSEnvelope2D( (CoordinateReferenceSystem) data );
}
throw new ClassCastException("Could not cast data to ReferencedEnvelope");
}
@Override
public Object visit( final ExcludeFilter filter, final Object data ) {
return null;
}
@Override
public Object visit( final IncludeFilter filter, final Object data ) {
if( data == null ) return null;
JTSEnvelope2D bbox = bbox( data );
// also consider making use of CRS extent?
Envelope world = new Envelope(Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY,
Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY);
bbox.expandToInclude( world );
return bbox;
}
@Override
public Object visit( final BBOX filter, final Object data ) {
if( data == null ) return null;
JTSEnvelope2D bbox = bbox( data );
// consider doing reprojection here into data CRS?
Envelope bounds = new Envelope(filter.getMinX(), filter.getMaxX(), filter.getMinY(), filter
.getMaxY());
bbox.expandToInclude(bounds);
return bbox;
}
/**
* Please note we are only visiting literals involved in spatial operations.
* @param expression , hopefully a Geometry or Envelope
* @param data Incoming BoundingBox (or Envelope or CRS)
*
* @return ReferencedEnvelope updated to reflect literal
*/
@Override
public Object visit( final Literal expression, final Object data ) {
if( data == null ) return null;
JTSEnvelope2D bbox = bbox( data );
Object value = expression.getValue();
if (value instanceof Geometry) {
Geometry geometry = (Geometry) value;
Envelope bounds = geometry.getEnvelopeInternal();
bbox.expandToInclude(bounds);
} else {
LOGGER.finer("LiteralExpression ignored!");
}
return bbox;
}
@Override
public Object visit( final Beyond filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Contains filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Crosses filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Disjoint filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final DWithin filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Equals filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Intersects filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Overlaps filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Touches filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit( final Within filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
}