| package org.apache.commons.rdf.impl.utils.graphmatching; |
| /* |
| * |
| * 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. |
| * |
| */ |
| |
| |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.Set; |
| |
| import org.apache.commons.rdf.BlankNode; |
| import org.apache.commons.rdf.Triple; |
| |
| public class Utils { |
| |
| static Set<BlankNode> getBNodes(Collection<Triple> s) { |
| Set<BlankNode> result = new HashSet<BlankNode>(); |
| for (Triple triple : s) { |
| if (triple.getSubject() instanceof BlankNode) { |
| result.add((BlankNode) triple.getSubject()); |
| } |
| if (triple.getObject() instanceof BlankNode) { |
| result.add((BlankNode) triple.getObject()); |
| } |
| } |
| return result; |
| } |
| |
| /** |
| * removes the common grounded triples from s1 and s2. returns false if |
| * a grounded triple is not in both sets, true otherwise |
| */ |
| static boolean removeGrounded(Collection<Triple> s1, Collection<Triple> s2) { |
| Iterator<Triple> triplesIter = s1.iterator(); |
| while (triplesIter.hasNext()) { |
| Triple triple = triplesIter.next(); |
| if (!isGrounded(triple)) { |
| continue; |
| } |
| if (!s2.remove(triple)) { |
| return false; |
| } |
| triplesIter.remove(); |
| } |
| //for efficiency we might skip this (redefine method) |
| for (Triple triple : s2) { |
| if (isGrounded(triple)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| private static boolean isGrounded(Triple triple) { |
| if (triple.getSubject() instanceof BlankNode) { |
| return false; |
| } |
| if (triple.getObject() instanceof BlankNode) { |
| return false; |
| } |
| return true; |
| } |
| |
| } |