/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.sparql.syntax.syntaxtransform ;
import org.apache.jena.atlas.lib.InternalErrorException ;
import org.apache.jena.graph.Node ;
import org.apache.jena.sparql.core.Var ;
import org.apache.jena.sparql.expr.Expr ;
import org.apache.jena.sparql.expr.ExprTransform ;
import org.apache.jena.sparql.expr.ExprVar ;
import org.apache.jena.sparql.expr.NodeValue ;
public class TransformElementLib {
public static Var applyVar(Var v, ExprTransform exprTransform) {
if ( exprTransform == null )
return v ;
ExprVar expr = new ExprVar(v) ;
Expr e = exprTransform.transform(expr) ;
if ( e instanceof ExprVar )
return ((ExprVar)e).asVar() ;
throw new InternalErrorException("Managed to turn a variable " + v + " into " + e) ;
}
public static Node apply(Node n, ExprTransform exprTransform) {
if ( exprTransform == null )
return n ;
Expr e = null ;
if ( Var.isVar(n) ) {
Var v = Var.alloc(n) ;
ExprVar expr = new ExprVar(v) ;
e = exprTransform.transform(expr) ;
} else {
NodeValue nv = NodeValue.makeNode(n) ;
e = exprTransform.transform(nv) ;
}
if ( e instanceof ExprVar )
return ((ExprVar)e).asVar() ;
if ( e instanceof NodeValue )
return ((NodeValue)e).asNode() ;
throw new InternalErrorException("Managed to turn a node " + n + " into " + e) ;
}
}