/*
* 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.util;
import java.util.HashMap ;
import java.util.Map ;
import org.apache.jena.graph.Node ;
/** Map nodes to nodes. */
public class NodeIsomorphismMap
{
private Map<Node, Node> map = new HashMap<>() ;
public NodeIsomorphismMap() {}
private Node get(Node key) { return map.get(key) ; }
private void put(Node key, Node value) { map.put(key, value) ; }
public boolean makeIsomorphic(Node n1, Node n2) {
if ( n1.isBlank() && n2.isBlank() ) {
Node other = get(n1) ;
if ( other == null ) {
put(n1, n2) ;
return true ;
}
return other.equals(n2) ;
}
return n1.equals(n2) ;
}
}