1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.eclipse.aether.graph;
20
21 /**
22 * A visitor for nodes of the dependency graph.
23 *
24 * @see DependencyNode#accept(DependencyVisitor)
25 */
26 public interface DependencyVisitor {
27
28 /**
29 * Notifies the visitor of a node visit before its children have been processed.
30 *
31 * @param node The dependency node being visited, must not be {@code null}.
32 * @return {@code true} to visit child nodes of the specified node as well, {@code false} to skip children.
33 */
34 boolean visitEnter(DependencyNode node);
35
36 /**
37 * Notifies the visitor of a node visit after its children have been processed. Note that this method is always
38 * invoked regardless whether any children have actually been visited.
39 *
40 * @param node The dependency node being visited, must not be {@code null}.
41 * @return {@code true} to visit siblings nodes of the specified node as well, {@code false} to skip siblings.
42 */
43 boolean visitLeave(DependencyNode node);
44 }