/*
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 org.openrdf.model.Literal;
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.model.BigdataValue;
import com.bigdata.rdf.model.BigdataValueFactory;
import com.bigdata.rdf.sparql.ast.FilterNode;
import com.bigdata.rdf.sparql.ast.GlobalAnnotations;
/**
* Return the language tag of the literal argument.
*/
@SuppressWarnings("rawtypes")
public class LangBOp extends IVValueExpression<IV>
implements INeedsMaterialization {
/**
*
*/
private static final long serialVersionUID = 7391999162162545704L;
// private static final transient Logger log = Logger.getLogger(LangBOp.class);
public LangBOp(final IValueExpression<? extends IV> x,
final GlobalAnnotations globals) {
super(x, globals);
}
/**
* Required shallow copy constructor.
*/
public LangBOp(final BOp[] args, final Map<String, Object> anns) {
super(args, anns);
if (args.length != 1 || args[0] == null)
throw new IllegalArgumentException();
if (getProperty(Annotations.NAMESPACE) == null)
throw new IllegalArgumentException();
}
/**
* Constructor required for {@link com.bigdata.bop.BOpUtility#deepCopy(FilterNode)}.
*/
public LangBOp(final LangBOp op) {
super(op);
}
@Override
public IV get(final IBindingSet bs) {
final Literal literal = getAndCheckLiteralValue(0, bs);
String langTag = literal.getLanguage();
if (langTag == null) {
langTag = "";
}
final BigdataValueFactory vf = getValueFactory();
final BigdataValue lang = vf.createLiteral(langTag);
return super.asIV(lang, bs);
}
@Override
public Requirement getRequirement() {
return INeedsMaterialization.Requirement.SOMETIMES;
}
}