/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2007-2008, 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.data.ogr;
import static org.bridj.Pointer.*;
import static org.geotools.data.ogr.bridj.OgrLibrary.*;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.bridj.Pointer;
import org.geotools.data.EmptyFeatureReader;
import org.geotools.data.FeatureReader;
import org.geotools.data.FilteringFeatureReader;
import org.geotools.data.Query;
import org.geotools.data.ReTypeFeatureReader;
import org.geotools.data.ogr.bridj.OGREnvelope;
import org.geotools.data.store.ContentEntry;
import org.geotools.data.store.ContentFeatureSource;
import org.geotools.data.store.ContentFeatureStore;
import org.geotools.factory.Hints;
import org.geotools.feature.simple.SimpleFeatureTypeBuilder;
import org.geotools.filter.FilterAttributeExtractor;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.opengis.feature.FeatureVisitor;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.feature.type.AttributeDescriptor;
import org.opengis.feature.type.GeometryDescriptor;
import org.opengis.filter.Filter;
import org.opengis.filter.sort.SortBy;
import org.opengis.filter.sort.SortOrder;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
import com.vividsolutions.jts.geom.CoordinateSequenceFactory;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryFactory;
/**
* FeatureSource for the OGR store, based on the {@link ContentFeatureStore} framework
*
* @author Andrea Aime - GeoSolutions
* @source $URL$
*/
@SuppressWarnings("rawtypes")
class OGRFeatureSource extends ContentFeatureSource {
public OGRFeatureSource(ContentEntry entry, Query query) {
super(entry, query);
}
@Override
public OGRDataStore getDataStore() {
return (OGRDataStore) super.getDataStore();
}
@Override
protected ReferencedEnvelope getBoundsInternal(Query query) throws IOException {
CoordinateReferenceSystem crs = getSchema().getCoordinateReferenceSystem();
// we need to know how much we can translate of the filter (the translator will also
// simplify the filter)
OGRFilterTranslator filterTx = new OGRFilterTranslator(getSchema(), query.getFilter());
if (Filter.EXCLUDE.equals(filterTx.getFilter())) {
// empty results
return new ReferencedEnvelope(crs);
} else if (!filterTx.isFilterFullySupported()) {
return null;
} else {
// encodable, we then encode and get the bounds
Pointer dataSource = null;
Pointer layer = null;
try {
// grab the layer
String typeName = getEntry().getTypeName();
dataSource = getDataStore().openOGRDataSource(false);
layer = getDataStore().openOGRLayer(dataSource, typeName);
// filter it
setLayerFilters(layer, filterTx);
Pointer<OGREnvelope> boundsPtr = allocate(OGREnvelope.class);
int code = OGR_L_GetExtent(layer, boundsPtr, 0);
if (code == OGRERR_FAILURE) {
return null;
} else {
OGREnvelope bounds = boundsPtr.get();
return new ReferencedEnvelope(bounds.MinX(), bounds.MaxX(), bounds.MinY(),
bounds.MaxY(), crs);
}
} finally {
OGRUtils.releaseLayer(layer);
OGRUtils.releaseDataSource(dataSource);
}
}
}
/**
* Sets the spatial filter and attribute filter on the specified layer
*
* @param layer
* @param filterTx
* @throws IOException
*/
private void setLayerFilters(Pointer layer, OGRFilterTranslator filterTx) throws IOException {
Geometry spatialFilter = filterTx.getSpatialFilter();
if (spatialFilter != null) {
Pointer ogrGeometry = new GeometryMapper.WKB(new GeometryFactory())
.parseGTGeometry(spatialFilter);
OGR_L_SetSpatialFilter(layer, ogrGeometry);
}
String attFilter = filterTx.getAttributeFilter();
if (attFilter != null) {
OGR_L_SetAttributeFilter(layer, pointerToCString(attFilter));
}
}
@Override
protected int getCountInternal(Query query) throws IOException {
// check how much we can encode
OGRFilterTranslator filterTx = new OGRFilterTranslator(getSchema(), query.getFilter());
if (Filter.EXCLUDE.equals(filterTx.getFilter())) {
return 0;
} else if (!filterTx.isFilterFullySupported()) {
// too expensive then
return -1;
} else {
// encode and count
Pointer dataSource = null;
Pointer layer = null;
try {
// grab the layer
String typeName = getEntry().getTypeName();
dataSource = getDataStore().openOGRDataSource(false);
layer = getDataStore().openOGRLayer(dataSource, typeName);
// filter it
setLayerFilters(layer, filterTx);
return OGR_L_GetFeatureCount(layer, 0);
} finally {
OGRUtils.releaseLayer(layer);
OGRUtils.releaseDataSource(dataSource);
}
}
}
@Override
protected FeatureReader<SimpleFeatureType, SimpleFeature> getReaderInternal(Query query)
throws IOException {
return getReaderInternal(null, null, query);
}
protected FeatureReader<SimpleFeatureType, SimpleFeature> getReaderInternal(Pointer dataSource,
Pointer layer, Query query) throws IOException {
// check how much we can encode
OGRFilterTranslator filterTx = new OGRFilterTranslator(getSchema(), query.getFilter());
if (Filter.EXCLUDE.equals(filterTx.getFilter())) {
return new EmptyFeatureReader<SimpleFeatureType, SimpleFeature>(getSchema());
}
// encode and count
boolean cleanup = false;
try {
// grab the data source
String typeName = getEntry().getTypeName();
if (dataSource == null) {
dataSource = getDataStore().openOGRDataSource(false);
cleanup = true;
}
// extract the post filter
Filter postFilter = null;
if (!filterTx.isFilterFullySupported()) {
postFilter = filterTx.getPostFilter();
}
// prepare the target schema
SimpleFeatureType sourceSchema = getSchema();
SimpleFeatureType querySchema = sourceSchema;
SimpleFeatureType targetSchema = sourceSchema;
String[] properties = query.getPropertyNames();
if (properties != null && properties.length > 0) {
targetSchema = SimpleFeatureTypeBuilder.retype(sourceSchema, properties);
querySchema = targetSchema;
// if we have a post filter we have to include in the queried features also the
// attribute needed to evaluate the post-filter
if (postFilter != null) {
Set<String> queriedAttributes = new HashSet<String>(Arrays.asList(properties));
FilterAttributeExtractor extraAttributeExtractor = new FilterAttributeExtractor();
postFilter.accept(extraAttributeExtractor, null);
Set<String> extraAttributeSet = new HashSet<String>(
extraAttributeExtractor.getAttributeNameSet());
extraAttributeSet.removeAll(queriedAttributes);
if (extraAttributeSet.size() > 0) {
String[] queryProperties = new String[properties.length
+ extraAttributeSet.size()];
System.arraycopy(properties, 0, queryProperties, 0, properties.length);
String[] extraAttributes = (String[]) extraAttributeSet
.toArray(new String[extraAttributeSet.size()]);
System.arraycopy(extraAttributes, 0, queryProperties, properties.length,
extraAttributes.length);
querySchema = SimpleFeatureTypeBuilder
.retype(sourceSchema, queryProperties);
}
}
}
// build the layer query and execute it
if (layer == null) {
String sql = getLayerSql(querySchema == sourceSchema ? null : querySchema,
filterTx.getAttributeFilter(), query.getSortBy());
Pointer spatialFilterPtr = null;
Geometry spatialFilter = filterTx.getSpatialFilter();
if (spatialFilter != null) {
spatialFilterPtr = new GeometryMapper.WKB(new GeometryFactory())
.parseGTGeometry(spatialFilter);
}
layer = OGR_DS_ExecuteSQL(dataSource, pointerToCString(sql), spatialFilterPtr, null);
if (layer == null) {
throw new IOException("Failed to query the source layer with SQL: " + sql);
}
} else {
setLayerFilters(layer, filterTx);
// would be nice, but it's not really working...
// setIgnoredFields(layer, querySchema, sourceSchema);
}
// see if we have a geometry factory to use
GeometryFactory gf = getGeometryFactory(query);
// build the reader
FeatureReader<SimpleFeatureType, SimpleFeature> reader = new OGRFeatureReader(
dataSource, layer, querySchema, sourceSchema, gf);
cleanup = false;
// do we have to post-filter?
if (!filterTx.isFilterFullySupported()) {
reader = new FilteringFeatureReader<SimpleFeatureType, SimpleFeature>(reader,
filterTx.getPostFilter());
if (targetSchema != querySchema) {
reader = new ReTypeFeatureReader(reader, targetSchema);
}
}
return reader;
} finally {
if (cleanup) {
OGRUtils.releaseLayer(layer);
OGRUtils.releaseDataSource(dataSource);
}
}
}
void setIgnoredFields(Pointer layer, SimpleFeatureType querySchema,
SimpleFeatureType sourceSchema) throws IOException {
if (OGR_L_TestCapability(layer, pointerToCString(OLCIgnoreFields)) != 0) {
List<String> ignoredFields = new ArrayList<String>();
ignoredFields.add("OGR_STYLE");
// if no geometry, skip it
if (querySchema.getGeometryDescriptor() == null) {
ignoredFields.add("OGR_GEOMETRY");
}
// process all other attributes
for (AttributeDescriptor ad : sourceSchema.getAttributeDescriptors()) {
if (!(ad instanceof GeometryDescriptor)) {
String name = ad.getLocalName();
if (querySchema.getDescriptor(name) == null) {
ignoredFields.add(name);
}
}
}
if (ignoredFields.size() > 0) {
// the list should be NULL terminated
ignoredFields.add(null);
String[] ignoredFieldsArr = (String[]) ignoredFields
.toArray(new String[ignoredFields.size()]);
Pointer<Pointer<Byte>> ifPtr = pointerToCStrings(ignoredFieldsArr);
OGRUtils.checkError(OGR_L_SetIgnoredFields(layer, ifPtr));
}
}
}
private String getLayerSql(SimpleFeatureType targetSchema, String attributeFilter,
SortBy[] sortBy) {
StringBuilder sb = new StringBuilder();
// list only the non geometry attributes
// select attributes
sb.append("SELECT FID, ");
if (targetSchema == null) {
sb.append("* ");
} else {
for (AttributeDescriptor attribute : targetSchema.getAttributeDescriptors()) {
if(attribute instanceof GeometryDescriptor) {
continue;
} else {
sb.append(attribute.getLocalName()).append(", ");
}
}
sb.setLength(sb.length() - 2);
sb.append(" ");
}
sb.append("FROM ").append("'").append(getSchema().getTypeName()).append("' ");
// attribute filter
if (attributeFilter != null) {
sb.append("WHERE ").append(attributeFilter);
}
// order by
if (sortBy != null && sortBy.length > 0) {
sb.append("ORDER BY ");
for (SortBy sort : sortBy) {
if (sort == SortBy.NATURAL_ORDER) {
sb.append("FID, ");
} else if (sort == SortBy.REVERSE_ORDER) {
sb.append("FID DESC, ");
} else {
sb.append(sort.getPropertyName().getPropertyName());
if (sort.getSortOrder() == SortOrder.DESCENDING) {
sb.append(" DESC");
}
sb.append(", ");
}
}
sb.setLength(sb.length() - 2);
}
return sb.toString();
}
GeometryFactory getGeometryFactory(Query query) {
Hints hints = query.getHints();
GeometryFactory gf = null;
if (hints != null) {
gf = (GeometryFactory) hints.get(Hints.JTS_GEOMETRY_FACTORY);
if (gf == null) {
// look for a coordinate sequence factory
CoordinateSequenceFactory csFactory = (CoordinateSequenceFactory) hints
.get(Hints.JTS_COORDINATE_SEQUENCE_FACTORY);
if (csFactory != null) {
gf = new GeometryFactory(csFactory);
}
}
}
if (gf == null) {
gf = new GeometryFactory();
}
return gf;
}
@Override
protected SimpleFeatureType buildFeatureType() throws IOException {
String typeName = getEntry().getTypeName();
String namespaceURI = getDataStore().getNamespaceURI();
Pointer dataSource = null;
Pointer layer = null;
try {
// grab the layer definition
dataSource = getDataStore().openOGRDataSource(false);
layer = getDataStore().openOGRLayer(dataSource, typeName);
// map to geotools feature type
return new FeatureTypeMapper().getFeatureType(layer, typeName, namespaceURI);
} finally {
OGRUtils.releaseLayer(layer);
OGRUtils.releaseDataSource(dataSource);
}
}
@Override
protected boolean canFilter() {
return true;
}
@Override
protected boolean canRetype() {
return true;
}
@Override
protected boolean canSort() {
return true;
}
@Override
protected boolean handleVisitor(Query query, FeatureVisitor visitor) throws IOException {
return super.handleVisitor(query, visitor);
}
}