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.internal.impl.synccontext.named;
20
21 import java.util.Collection;
22
23 import org.eclipse.aether.RepositorySystemSession;
24 import org.eclipse.aether.artifact.Artifact;
25 import org.eclipse.aether.metadata.Metadata;
26
27 /**
28 * Component mapping lock names to passed in artifacts and metadata as required.
29 */
30 public interface NameMapper {
31 /**
32 * Returns {@code true} if lock names returned by this lock name mapper are file system friendly, can be used
33 * as file names and paths.
34 *
35 * @since 1.9.0
36 */
37 boolean isFileSystemFriendly();
38
39 /**
40 * Creates (opaque) names for passed in artifacts and metadata. Returned collection has max size of sum of the
41 * passed in artifacts and metadata collections, or less. If an empty collection is returned, there will be no
42 * locking happening. Never returns {@code null}. The resulting collection MUST BE "stable" (always sorted by
43 * same criteria) to avoid deadlocks by acquiring locks in same order, essentially disregarding the order of
44 * the input collections.
45 * <p>
46 * There is no requirement of any kind of "parity" between input element count (sum of two collections, that is)
47 * and output collection size, just the returned upper size limit is defined (sum of the passed in two collections
48 * size). If returned collection is empty, no locking will happen, if single element, one lock will be used, if two
49 * then two named locks will be used etc.
50 * <p>
51 * Note: name mapper must not use same string for artifacts and metadata, so even the simplest possible
52 * implementation like {@link StaticNameMapper} uses two different static strings.
53 */
54 Collection<String> nameLocks(
55 RepositorySystemSession session,
56 Collection<? extends Artifact> artifacts,
57 Collection<? extends Metadata> metadatas);
58 }