/*
* JBoss DNA (http://www.jboss.org/dna)
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
* See the AUTHORS.txt file in the distribution for a full listing of
* individual contributors.
*
* JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
* is licensed to you under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* JBoss DNA 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.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.dna.graph.query.process;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.jboss.dna.graph.Location;
import org.jboss.dna.graph.query.QueryContext;
import org.jboss.dna.graph.query.QueryResults.Columns;
import org.jboss.dna.graph.query.model.Column;
import org.jboss.dna.graph.query.model.Constraint;
import org.jboss.dna.graph.query.model.Limit;
import org.jboss.dna.graph.query.model.SelectorName;
import org.jboss.dna.graph.query.plan.PlanNode;
import org.jboss.dna.graph.query.plan.PlanNode.Property;
import org.jboss.dna.graph.query.plan.PlanNode.Type;
import org.jboss.dna.graph.query.validate.Schemata;
/**
* A reusable base class for {@link ProcessingComponent} implementations that does everything except obtain the correct
* {@link Location} objects for the query results.
*/
public abstract class AbstractAccessComponent extends ProcessingComponent {
protected final PlanNode accessNode;
protected final SelectorName sourceName;
protected final List<Column> projectedColumns;
protected final List<Constraint> andedConstraints;
protected final Limit limit;
protected AbstractAccessComponent( QueryContext context,
Columns columns,
PlanNode accessNode ) {
super(context, columns);
this.accessNode = accessNode;
// Find the table name; should be
PlanNode source = accessNode.findAtOrBelow(Type.SOURCE);
if (source != null) {
this.sourceName = source.getProperty(Property.SOURCE_NAME, SelectorName.class);
// if (!AllNodes.ALL_NODES_NAME.equals(this.sourceName)) {
// throw new IllegalArgumentException();
// }
} else {
throw new IllegalArgumentException();
}
// Find the project ...
PlanNode project = accessNode.findAtOrBelow(Type.PROJECT);
if (project != null) {
List<Column> projectedColumns = project.getPropertyAsList(Property.PROJECT_COLUMNS, Column.class);
if (projectedColumns != null) {
this.projectedColumns = projectedColumns;
} else {
// Get the columns from the source columns ...
List<Schemata.Column> schemataColumns = source.getPropertyAsList(Property.SOURCE_COLUMNS, Schemata.Column.class);
this.projectedColumns = new ArrayList<Column>(schemataColumns.size());
for (Schemata.Column schemataColumn : schemataColumns) {
String columnName = schemataColumn.getName();
// PropertyType type = schemataColumn.getPropertyType();
String propertyName = columnName;
Column column = new Column(sourceName, propertyName, columnName);
this.projectedColumns.add(column);
}
}
} else {
throw new IllegalArgumentException();
}
// Add the criteria ...
List<Constraint> andedConstraints = null;
for (PlanNode select : accessNode.findAllAtOrBelow(Type.SELECT)) {
Constraint selectConstraint = select.getProperty(Property.SELECT_CRITERIA, Constraint.class);
if (andedConstraints == null) andedConstraints = new ArrayList<Constraint>();
andedConstraints.add(selectConstraint);
}
this.andedConstraints = andedConstraints != null ? andedConstraints : Collections.<Constraint>emptyList();
// Find the limit ...
Limit limit = Limit.NONE;
PlanNode limitNode = accessNode.findAtOrBelow(Type.LIMIT);
if (limitNode != null) {
Integer count = limitNode.getProperty(Property.LIMIT_COUNT, Integer.class);
if (count != null) limit = limit.withRowLimit(count.intValue());
Integer offset = limitNode.getProperty(Property.LIMIT_OFFSET, Integer.class);
if (offset != null) limit = limit.withOffset(offset.intValue());
}
this.limit = limit;
}
}