/*
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
*/
package com.bigdata.rdf.internal.constraints;
import java.util.Map;
import com.bigdata.bop.BOp;
import com.bigdata.bop.IBindingSet;
import com.bigdata.bop.IVariable;
import com.bigdata.bop.NV;
import com.bigdata.rdf.error.SparqlTypeErrorException;
import com.bigdata.rdf.internal.IV;
import com.bigdata.rdf.sparql.ast.GlobalAnnotations;
/**
* Imposes the constraint <code>bound(x)</code> for the variable x.
*/
public class IsBoundBOp extends XSDBooleanIVValueExpression {
/**
*
*/
private static final long serialVersionUID = -7408654639183330874L;
public IsBoundBOp(final IVariable<IV> x) {
this(new BOp[] { x }, BOp.NOANNS);
}
/**
* Required shallow copy constructor.
*/
public IsBoundBOp(final BOp[] args, final Map<String, Object> anns) {
super(args, anns);
if (args.length != 1 || args[0] == null)
throw new IllegalArgumentException();
}
/**
* Constructor required for {@link com.bigdata.bop.BOpUtility#deepCopy(FilterNode)}.
*/
public IsBoundBOp(final IsBoundBOp op) {
super(op);
}
/**
* <pre>
* Returns true if var is bound to a value. Returns false otherwise.
* Variables with the value NaN or INF are considered bound.
* </pre>
*
* @see http://www.w3.org/TR/sparql11-query/#func-bound
*/
public boolean accept(final IBindingSet bs) {
try {
return get(0).get(bs) != null;
} catch (SparqlTypeErrorException ex) {
// Not bound.
return false;
}
}
}