/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.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.geotools.filter.visitor;
import java.util.logging.Logger;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.opengis.filter.And;
import org.opengis.filter.ExcludeFilter;
import org.opengis.filter.Filter;
import org.opengis.filter.Id;
import org.opengis.filter.IncludeFilter;
import org.opengis.filter.Not;
import org.opengis.filter.Or;
import org.opengis.filter.PropertyIsBetween;
import org.opengis.filter.PropertyIsEqualTo;
import org.opengis.filter.PropertyIsGreaterThan;
import org.opengis.filter.PropertyIsGreaterThanOrEqualTo;
import org.opengis.filter.PropertyIsLessThan;
import org.opengis.filter.PropertyIsLessThanOrEqualTo;
import org.opengis.filter.PropertyIsLike;
import org.opengis.filter.PropertyIsNotEqualTo;
import org.opengis.filter.PropertyIsNull;
import org.opengis.filter.expression.Add;
import org.opengis.filter.expression.Divide;
import org.opengis.filter.expression.Function;
import org.opengis.filter.expression.Literal;
import org.opengis.filter.expression.Multiply;
import org.opengis.filter.expression.NilExpression;
import org.opengis.filter.expression.PropertyName;
import org.opengis.filter.expression.Subtract;
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;
/**
* 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 an empty envelope
* <li>Filter.INCLUDES will result in a "world" envelope with range Double.NEGATIVE_INFINITY to
* Double.POSITIVE_INFINITY for each axis.
* <li>all other non spatial filters will result in a world envelope
* <li>combinations in and will return the intersection of the envelopes, or an empty envelope
* if an exclude is in the mix, or null if the and is mixing non spatial filters</li>
* <li>combinations in or will return the intersection of
* </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
*
*
* @source $URL$
*/
public class ExtractBoundsFilterVisitor extends NullFilterVisitor {
static public NullFilterVisitor BOUNDS_VISITOR = new ExtractBoundsFilterVisitor();
private static Logger LOGGER = org.geotools.util.logging.Logging
.getLogger("org.geotools.index.rtree");
/**
* 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 ReferencedEnvelope bbox( Object data ) {
if( data == null ){
return null;
}
else if (data instanceof ReferencedEnvelope) {
return (ReferencedEnvelope) data;
}
else if (data instanceof Envelope){
return new ReferencedEnvelope( (Envelope) data, null );
}
else if (data instanceof CoordinateReferenceSystem){
return new ReferencedEnvelope( (CoordinateReferenceSystem) data );
}
throw new ClassCastException("Could not cast data to ReferencedEnvelope");
}
public Object visit( ExcludeFilter filter, Object data ) {
return new Envelope();
}
public Object visit( IncludeFilter filter, Object data ) {
return infinity();
}
Envelope infinity() {
return new Envelope(Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY,
Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY);
}
public Object visit( BBOX filter, Object data ) {
ReferencedEnvelope bbox = bbox( data );
// consider doing reprojection here into data CRS?
Envelope bounds = new Envelope(filter.getMinX(), filter.getMaxX(), filter.getMinY(), filter
.getMaxY());
if(bbox != null) {
bbox.expandToInclude(bounds);
return bbox;
} else {
return bbox(bounds);
}
}
/**
* Please note we are only visiting literals involved in spatial operations.
* @param literal, hopefully a Geometry or Envelope
* @param data Incoming BoundingBox (or Envelope or CRS)
*
* @return ReferencedEnvelope updated to reflect literal
*/
public Object visit( Literal expression, Object data ) {
ReferencedEnvelope bbox = bbox( data );
Object value = expression.getValue();
if (value instanceof Geometry) {
Geometry geometry = (Geometry) value;
Envelope bounds = geometry.getEnvelopeInternal();
if(bbox != null) {
bbox.expandToInclude(bounds);
return bbox;
} else {
return bbox(bounds);
}
} else {
LOGGER.finer("LiteralExpression ignored!");
}
return bbox;
}
@Override
public Object visit(And filter, Object data) {
Envelope mixed = infinity();
for (Filter f : filter.getChildren()) {
Envelope env = (Envelope) f.accept(this, data);
mixed = mixed.intersection(env);
}
return mixed;
}
public Object visit(Not filter, Object data) {
// no matter what we have to return an infinite envelope
// rationale
// !(finite envelope) -> an unbounded area -> infinite
// !(non spatial filter) -> infinite (no spatial concern)
// !(infinite) -> ... infinite, as the first infinite could be the result
// of !(finite envelope)
return infinity();
}
@Override
public Object visit(Or filter, Object data) {
Envelope mixed = new Envelope();
for (Filter f : filter.getChildren()) {
Envelope env = (Envelope) f.accept(this, data);
mixed.expandToInclude(env);
}
return mixed;
}
public Object visit( Beyond filter, Object data ) {
// beyond a certain distance from a finite object, no way to limit it
return infinity();
}
public Object visit( Contains filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
public Object visit( Crosses filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
public Object visit( Disjoint filter, Object data ) {
// disjoint does not define a rectangle, but a hole in the
// Cartesian plane, no way to limit it
return infinity();
}
public Object visit( DWithin filter, Object data ) {
ReferencedEnvelope bbox = bbox( data );
// we have to take the reference geometry bbox and
// expand it by the distance.
// We ignore the unit of measure for the moment
Literal geometry = null;
if(filter.getExpression1() instanceof PropertyName
&& filter.getExpression2() instanceof Literal) {
geometry = (Literal) filter.getExpression2();
} if(filter.getExpression2() instanceof PropertyName
&& filter.getExpression1() instanceof Literal) {
geometry = (Literal) filter.getExpression2();
}
// we cannot desume a bbox from this filter
if(geometry == null) {
return infinity();
}
Geometry geom = geometry.evaluate(null, Geometry.class);
if(geom == null) {
return infinity();
}
Envelope env = geom.getEnvelopeInternal();
env.expandBy(filter.getDistance());
if(bbox != null) {
bbox.expandToInclude(env);
return bbox;
} else {
return bbox(env);
}
}
public Object visit( Equals filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
public Object visit( Intersects filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
public Object visit( Overlaps filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
public Object visit( Touches filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
public Object visit( Within filter, Object data ) {
data = filter.getExpression1().accept(this, data);
data = filter.getExpression2().accept(this, data);
return data;
}
@Override
public Object visit(Add expression, Object data) {
return infinity();
}
@Override
public Object visit(Divide expression, Object data) {
return infinity();
}
@Override
public Object visit(Function expression, Object data) {
return infinity();
}
@Override
public Object visit(Id filter, Object data) {
return infinity();
}
@Override
public Object visit(Multiply expression, Object data) {
return infinity();
}
@Override
public Object visit(NilExpression expression, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsBetween filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsEqualTo filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsGreaterThan filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsGreaterThanOrEqualTo filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsLessThan filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsLessThanOrEqualTo filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsLike filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsNotEqualTo filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyIsNull filter, Object data) {
return infinity();
}
@Override
public Object visit(PropertyName expression, Object data) {
return null;
}
@Override
public Object visit(Subtract expression, Object data) {
return infinity();
}
@Override
public Object visitNullFilter(Object data) {
return infinity();
}
}