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.util.graph.manager;
20
21 import org.eclipse.aether.collection.DependencyCollectionContext;
22 import org.eclipse.aether.collection.DependencyManagement;
23 import org.eclipse.aether.collection.DependencyManager;
24 import org.eclipse.aether.graph.Dependency;
25
26 import static java.util.Objects.requireNonNull;
27
28 /**
29 * A dependency manager that does not do any dependency management.
30 */
31 public final class NoopDependencyManager implements DependencyManager {
32
33 /**
34 * A ready-made instance of this dependency manager which can safely be reused throughout an entire application
35 * regardless of multi-threading.
36 */
37 public static final DependencyManager INSTANCE = new NoopDependencyManager();
38
39 /**
40 * Creates a new instance of this dependency manager. Usually, {@link #INSTANCE} should be used instead.
41 */
42 public NoopDependencyManager() {}
43
44 public DependencyManager deriveChildManager(DependencyCollectionContext context) {
45 requireNonNull(context, "context cannot be null");
46 return this;
47 }
48
49 public DependencyManagement manageDependency(Dependency dependency) {
50 requireNonNull(dependency, "dependency cannot be null");
51 return null;
52 }
53
54 @Override
55 public boolean equals(Object obj) {
56 if (this == obj) {
57 return true;
58 } else if (null == obj || !getClass().equals(obj.getClass())) {
59 return false;
60 }
61 return true;
62 }
63
64 @Override
65 public int hashCode() {
66 return getClass().hashCode();
67 }
68 }