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.apache.maven.api;
20
21 import org.apache.maven.api.annotations.Consumer;
22 import org.apache.maven.api.annotations.Experimental;
23 import org.apache.maven.api.annotations.Nonnull;
24
25 /**
26 * Defines a hierarchical visitor for collecting dependency node trees.
27 *
28 * @since 4.0.0
29 */
30 @Experimental
31 @Consumer
32 public interface NodeVisitor {
33 /**
34 * Starts the visit to the specified dependency node.
35 *
36 * @param node the dependency node to visit
37 * @return <code>true</code> to visit the specified dependency node's children, <code>false</code> to skip the
38 * specified dependency node's children and proceed to its next sibling
39 */
40 boolean enter(@Nonnull Node node);
41
42 /**
43 * Ends the visit to the specified dependency node.
44 *
45 * @param node the dependency node to visit
46 * @return <code>true</code> to visit the specified dependency node's next sibling, <code>false</code> to skip the
47 * specified dependency node's next siblings and proceed to its parent
48 */
49 boolean leave(@Nonnull Node node);
50 }