/*
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.IValueExpression;
import com.bigdata.rdf.internal.IV;
import com.bigdata.rdf.internal.impl.literal.XSDBooleanIV;
import com.bigdata.rdf.sparql.ast.FilterNode;
/**
* Base class for RDF value expression BOps that happen to evaluate to an
* {@link XSDBooleanIV}. These are operators such as Compare, Is*, And, Or, etc.
*/
public abstract class XSDBooleanIVValueExpression extends
IVValueExpression<XSDBooleanIV> {
/**
*
*/
private static final long serialVersionUID = -7068219781217676085L;
/**
* If the operand is not known to evaluate to a boolean, wrap it with an
* {@link EBVBOp}.
*
* @return An operand which is known to evaluate to an {@link XSDBooleanIV}.
*/
protected static final XSDBooleanIVValueExpression wrap(
final IValueExpression<? extends IV> ve) {
return ve instanceof XSDBooleanIVValueExpression ?
(XSDBooleanIVValueExpression) ve : new EBVBOp(ve);
}
/**
* None of the xsd:boolean IV value expressions require access to the
* ValueFactory or LexiconConfiguration.
*/
@Override
protected boolean areGlobalsRequired() {
return false;
}
/**
* Required shallow copy constructor.
*/
public XSDBooleanIVValueExpression(final BOp[] args,
final Map<String, Object> anns) {
super(args, anns);
}
/**
* Constructor required for {@link com.bigdata.bop.BOpUtility#deepCopy(FilterNode)}.
*/
public XSDBooleanIVValueExpression(final XSDBooleanIVValueExpression op) {
super(op);
}
/**
* Delegates to {@link #accept(IBindingSet)}.
*/
@SuppressWarnings("rawtypes")
@Override
final public XSDBooleanIV get(final IBindingSet bs) {
return XSDBooleanIV.valueOf(accept(bs));
}
/**
* Implement this method.
*
* @param bs
* The source solution.
* @return <code>true</code> iff the function accepts the solution.
*/
protected abstract boolean accept(final IBindingSet bs);
}