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.version;
20
21 import java.util.Iterator;
22
23 import org.eclipse.aether.collection.DependencyCollectionContext;
24 import org.eclipse.aether.collection.VersionFilter;
25 import org.eclipse.aether.version.Version;
26
27 /**
28 * A version filter that excludes any version except the lowest one.
29 *
30 * @since 2.0.0
31 */
32 public final class LowestVersionFilter implements VersionFilter {
33
34 /**
35 * Creates a new instance of this version filter.
36 */
37 public LowestVersionFilter() {}
38
39 @Override
40 public void filterVersions(VersionFilterContext context) {
41 Iterator<Version> it = context.iterator();
42 if (it.hasNext()) {
43 it.next();
44 while (it.hasNext()) {
45 it.next();
46 it.remove();
47 }
48 }
49 }
50
51 @Override
52 public VersionFilter deriveChildFilter(DependencyCollectionContext context) {
53 return this;
54 }
55
56 @Override
57 public boolean equals(Object obj) {
58 if (this == obj) {
59 return true;
60 } else if (null == obj || !getClass().equals(obj.getClass())) {
61 return false;
62 }
63 return true;
64 }
65
66 @Override
67 public int hashCode() {
68 return getClass().hashCode();
69 }
70 }