001package org.eclipse.aether.internal.impl.synccontext.named; 002 003/* 004 * Licensed to the Apache Software Foundation (ASF) under one 005 * or more contributor license agreements. See the NOTICE file 006 * distributed with this work for additional information 007 * regarding copyright ownership. The ASF licenses this file 008 * to you under the Apache License, Version 2.0 (the 009 * "License"); you may not use this file except in compliance 010 * with the License. You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, 015 * software distributed under the License is distributed on an 016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 017 * KIND, either express or implied. See the License for the 018 * specific language governing permissions and limitations 019 * under the License. 020 */ 021 022import java.util.Collection; 023 024import org.eclipse.aether.RepositorySystemSession; 025import org.eclipse.aether.artifact.Artifact; 026import org.eclipse.aether.metadata.Metadata; 027 028/** 029 * Component mapping lock names to passed in artifacts and metadata as required. 030 */ 031public interface NameMapper 032{ 033 /** 034 * Returns {@code true} if lock names returned by this lock name mapper are file system friendly, can be used 035 * as file names and paths. 036 * 037 * @since 1.9.0 038 */ 039 boolean isFileSystemFriendly(); 040 041 /** 042 * Creates (opaque) names for passed in artifacts and metadata. Returned collection has max size of sum of the 043 * passed in artifacts and metadata collections, or less. If an empty collection is returned, there will be no 044 * locking happening. Never returns {@code null}. The resulting collection MUST BE "stable" (always sorted by 045 * same criteria) to avoid deadlocks by acquiring locks in same order, essentially disregarding the order of 046 * the input collections. 047 * <p> 048 * There is no requirement of any kind of "parity" between input element count (sum of two collections, that is) 049 * and output collection size, just the returned upper size limit is defined (sum of the passed in two collections 050 * size). If returned collection is empty, no locking will happen, if single element, one lock will be used, if two 051 * then two named locks will be used etc. 052 */ 053 Collection<String> nameLocks( RepositorySystemSession session, 054 Collection<? extends Artifact> artifacts, 055 Collection<? extends Metadata> metadatas ); 056}