001package org.eclipse.aether.spi.connector.checksum; 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.List; 023import java.util.Map; 024 025import org.eclipse.aether.RepositorySystemSession; 026import org.eclipse.aether.spi.connector.ArtifactDownload; 027 028/** 029 * Component able to provide (expected) checksums to connector beforehand the download happens. Checksum provided by 030 * this component are of kind {@link org.eclipse.aether.spi.connector.checksum.ChecksumPolicy.ChecksumKind#PROVIDED}. 031 * 032 * @since 1.8.0 033 */ 034public interface ProvidedChecksumsSource 035{ 036 /** 037 * May return the provided checksums (for given artifact transfer) from source other than remote repository, or 038 * {@code null} if it have no checksums available for given transfer. Provided checksums are "opt-in" for 039 * transfer, in a way IF they are available upfront, they will be enforced according to checksum policy 040 * in effect. Otherwise, provided checksum verification is completely left out. 041 * <p> 042 * For enabled provided checksum source is completely acceptable to return {@code null} values, as that carries 043 * the meaning "nothing to add here", as there are no checksums to be provided upfront transfer. Semantically, this 044 * is equivalent to returning empty map, but signals the intent better. 045 * 046 * @param transfer The transfer that is about to be executed. 047 * @param checksumAlgorithmFactories The checksum algorithms that are expected. 048 * @return Map of expected checksums, or {@code null}. 049 */ 050 Map<String, String> getProvidedArtifactChecksums( RepositorySystemSession session, 051 ArtifactDownload transfer, 052 List<ChecksumAlgorithmFactory> checksumAlgorithmFactories ); 053}