/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Aug 26, 2011
*/
package com.bigdata.rdf.sparql.ast;
import java.util.Map;
import org.openrdf.model.URI;
import com.bigdata.bop.BOp;
/**
* A special function node for modeling value expression nodes which are
* evaluated against an inner graph expression, such as EXISTS and NOT EXISTS.
* Another possibility is IN(subSelect), where IN is evaluated against the
* subquery result.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
*/
abstract public class SubqueryFunctionNodeBase extends FunctionNode implements
IGraphPatternContainer {
/**
*
*/
private static final long serialVersionUID = 1L;
interface Annotations extends FunctionNode.Annotations,
IGraphPatternContainer.Annotations {
/**
* Used to specify the query plan for FILTER (NOT) EXISTS. There are two
* basic plans: vectored sub-plan and subquery with LIMIT ONE. Each plan
* has its advantages.
* <p>
* Note: This annotation gets propagated to the {@link SubqueryRoot}
* when the FILTER (NOT) EXISTS is turned into an ASK subquery.
*
* @see FilterExistsModeEnum
* @see <a href="http://trac.blazegraph.com/ticket/988"> bad performance
* for FILTER EXISTS </a>
*/
String FILTER_EXISTS = QueryHints.FILTER_EXISTS;
FilterExistsModeEnum DEFAULT_FILTER_EXISTS = QueryHints.DEFAULT_FILTER_EXISTS;
}
/**
* Constructor required for {@link com.bigdata.bop.BOpUtility#deepCopy(FilterNode)}.
*/
public SubqueryFunctionNodeBase(final SubqueryFunctionNodeBase op) {
super(op);
}
/**
* Required shallow copy constructor.
*/
public SubqueryFunctionNodeBase(final BOp[] args,
final Map<String, Object> anns) {
super(args, anns);
}
/**
* @param anonvar
* An anonymous variable which will be bound by an ASK subquery.
* @param graphPattern
* The inner value of the EXISTS function.
*/
protected SubqueryFunctionNodeBase(final URI functionURI,
final VarNode anonvar,
final GraphPatternGroup<IGroupMemberNode> graphPattern) {
super(functionURI, null/* scalarValues */,
new ValueExpressionNode[] { anonvar });
if (anonvar == null)
throw new IllegalArgumentException();
if (graphPattern == null)
throw new IllegalArgumentException();
setGraphPattern(graphPattern);
}
@Override
@SuppressWarnings("unchecked")
public GraphPatternGroup<IGroupMemberNode> getGraphPattern() {
return (GraphPatternGroup<IGroupMemberNode>) getProperty(Annotations.GRAPH_PATTERN);
}
@Override
public void setGraphPattern(
final GraphPatternGroup<IGroupMemberNode> graphPattern) {
/*
* Clear the parent reference on the new where clause.
*
* Note: This handles cases where a join group is lifted into a named
* subquery. If we do not clear the parent reference on the lifted join
* group it will still point back to its parent in the original join
* group.
*/
graphPattern.setParent(null);
setProperty(Annotations.GRAPH_PATTERN, graphPattern);
}
/**
*
* @see Annotations#FILTER_EXISTS
*/
public void setFilterExistsMode(final FilterExistsModeEnum newVal) {
setProperty(Annotations.FILTER_EXISTS, newVal);
}
/**
* @see Annotations#FILTER_EXISTS
*/
public FilterExistsModeEnum getFilterExistsMode() {
return getProperty(Annotations.FILTER_EXISTS,
Annotations.DEFAULT_FILTER_EXISTS);
}
@Override
protected void annotationValueToString(final StringBuilder sb, final BOp val, int i) {
sb.append(val.toString(i));
}
}