001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.eclipse.aether.transport.http;
020
021import java.util.Map;
022
023import org.apache.http.HttpResponse;
024import org.apache.http.client.HttpResponseException;
025import org.apache.http.client.methods.HttpUriRequest;
026
027/**
028 * A component extracting included checksums from response of artifact request.
029 *
030 * @since 1.8.0
031 */
032public abstract class ChecksumExtractor {
033    /**
034     * Prepares request, if needed.
035     */
036    public void prepareRequest(HttpUriRequest request) {
037        // nothing
038    }
039
040    /**
041     * May control is request to be retried with checksum extractors disabled.
042     */
043    public boolean retryWithoutExtractor(HttpResponseException exception) {
044        return false; // nothing, usually tied to prepareRequest
045    }
046
047    /**
048     * Tries to extract checksums from response headers, if present, otherwise returns {@code null}.
049     */
050    public abstract Map<String, String> extractChecksums(HttpResponse response);
051}