/**
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 org.openrdf.model.URI;
import org.openrdf.model.Value;
import org.openrdf.query.algebra.Compare.CompareOp;
import com.bigdata.bop.BOp;
import com.bigdata.bop.IBindingSet;
import com.bigdata.bop.IValueExpression;
import com.bigdata.bop.NV;
import com.bigdata.rdf.error.SparqlTypeErrorException;
import com.bigdata.rdf.internal.IV;
/**
* Compare two terms for exact equality.
*/
public class SameTermBOp extends XSDBooleanIVValueExpression
implements INeedsMaterialization {
/**
*
*/
private static final long serialVersionUID = 1L;
public interface Annotations extends
XSDBooleanIVValueExpression.Annotations {
/**
* The compare operator, which is a {@link CompareOp} enum value. Must
* be either {@link CompareOp#EQ} or {@link CompareOp#NE}.
*/
String OP = CompareBOp.Annotations.OP;
}
/**
* Constructor for sameTerm using {@link CompareOp#EQ}.
*/
@SuppressWarnings("rawtypes")
public SameTermBOp(
final IValueExpression<? extends IV> left,
final IValueExpression<? extends IV> right) {
this(left, right, CompareOp.EQ);
}
/**
* Constructor for sameTerm using either {@link CompareOp#EQ} or
* {@link CompareOp#NE}.
*
* @param left
* @param right
* @param op
*/
@SuppressWarnings("rawtypes")
public SameTermBOp(final IValueExpression<? extends IV> left,
final IValueExpression<? extends IV> right, final CompareOp op) {
this(new BOp[] { left, right }, NV.asMap(Annotations.OP, op));
}
/**
* Required shallow copy constructor.
*/
public SameTermBOp(final BOp[] args, final Map<String, Object> anns) {
super(args, anns);
if (args.length != 2 || args[0] == null || args[1] == null)
throw new IllegalArgumentException();
final CompareOp op = (CompareOp) getRequiredProperty(Annotations.OP);
if (!(op == CompareOp.EQ || op == CompareOp.NE))
throw new IllegalArgumentException();
}
/**
* Constructor required for {@link com.bigdata.bop.BOpUtility#deepCopy(FilterNode)}.
*/
public SameTermBOp(final SameTermBOp op) {
super(op);
}
@Override
public INeedsMaterialization.Requirement getRequirement() {
return INeedsMaterialization.Requirement.SOMETIMES;
}
public boolean accept(final IBindingSet bs) {
@SuppressWarnings("rawtypes")
final IV left = get(0).get(bs);
// not yet bound
if (left == null)
throw new SparqlTypeErrorException();
@SuppressWarnings("rawtypes")
final IV right = get(1).get(bs);
// not yet bound
if (right == null)
throw new SparqlTypeErrorException();
final CompareOp op = (CompareOp) getRequiredProperty(Annotations.OP);
switch (op) {
case EQ:
return compare(left, right);
default:
return !compare(left, right);
}
}
private static boolean compare(final IV iv1, final IV iv2) {
if (iv1.isNullIV() || iv2.isNullIV()) {
final Value val1 = asValue(iv1);
final Value val2 = asValue(iv2);
if (val1 instanceof URI && val2 instanceof URI) {
return val1.stringValue().equals(val2.stringValue());
} else if (val1 instanceof Literal && val2 instanceof Literal) {
final Literal lit1 = (Literal) val1;
final Literal lit2 = (Literal) val2;
return equals(lit1.getLabel(), lit2.getLabel()) &&
equals(lit1.getDatatype(), lit2.getDatatype()) &&
equals(lit1.getLanguage(), lit2.getLanguage());
} else {
return false;
}
} else {
return iv1.equals(iv2);
}
}
private static boolean equals(final Object o1, final Object o2) {
if (o1 == null && o2 == null)
return true;
if (o1 == null || o2 == null)
return false;
return o1.equals(o2);
}
}