| /* |
| * 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.openjpa.lib.graph; |
| |
| /** |
| * <p>A helper interface that allows third parties to be notified of |
| * graph events during graph traversals</p> |
| * |
| * @author Steve Kim |
| * @since 1.0.0 |
| * @nojavadoc |
| */ |
| public interface GraphVisitor { |
| |
| /** |
| * May not be called. The meaning of this method is dependent |
| * on the traversal being used. See each appropriate graph |
| * walker for details. |
| */ |
| public void nodeSeen(Object node); |
| |
| /** |
| * will only be called once per node |
| */ |
| public void nodeVisited(Object node); |
| |
| /** |
| * may visit the node twice (both sides) |
| */ |
| public void edgeVisited(Edge edge); |
| } |