1 package org.eclipse.aether.util.graph.manager;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import org.eclipse.aether.collection.DependencyCollectionContext;
23 import org.eclipse.aether.collection.DependencyManagement;
24 import org.eclipse.aether.collection.DependencyManager;
25 import org.eclipse.aether.graph.Dependency;
26
27 import static java.util.Objects.requireNonNull;
28
29 /**
30 * A dependency manager that does not do any dependency management.
31 */
32 public final class NoopDependencyManager
33 implements DependencyManager
34 {
35
36 /**
37 * A ready-made instance of this dependency manager which can safely be reused throughout an entire application
38 * regardless of multi-threading.
39 */
40 public static final DependencyManager INSTANCE = new NoopDependencyManager();
41
42 /**
43 * Creates a new instance of this dependency manager. Usually, {@link #INSTANCE} should be used instead.
44 */
45 public NoopDependencyManager()
46 {
47 }
48
49 public DependencyManager deriveChildManager( DependencyCollectionContext context )
50 {
51 requireNonNull( context, "context cannot be null" );
52 return this;
53 }
54
55 public DependencyManagement manageDependency( Dependency dependency )
56 {
57 requireNonNull( dependency, "dependency cannot be null" );
58 return null;
59 }
60
61 @Override
62 public boolean equals( Object obj )
63 {
64 if ( this == obj )
65 {
66 return true;
67 }
68 else if ( null == obj || !getClass().equals( obj.getClass() ) )
69 {
70 return false;
71 }
72 return true;
73 }
74
75 @Override
76 public int hashCode()
77 {
78 return getClass().hashCode();
79 }
80
81 }