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.spi.connector.layout;
020
021import org.eclipse.aether.RepositorySystemSession;
022import org.eclipse.aether.repository.RemoteRepository;
023import org.eclipse.aether.transfer.NoRepositoryLayoutException;
024
025/**
026 * A factory to obtain repository layouts. A repository layout is responsible to map an artifact or some metadata to a
027 * URI relative to the repository root where the resource resides. When the repository system needs to access a given
028 * remote repository, it iterates the registered factories in descending order of their priority and calls
029 * {@link #newInstance(RepositorySystemSession, RemoteRepository)} on them. The first layout returned by a factory will
030 * then be used for transferring artifacts/metadata.
031 */
032public interface RepositoryLayoutFactory {
033
034    /**
035     * Tries to create a repository layout for the specified remote repository. Typically, a factory will inspect
036     * {@link RemoteRepository#getContentType()} to determine whether it can handle a repository.
037     *
038     * @param session The repository system session from which to configure the layout, must not be {@code null}.
039     * @param repository The remote repository to create a layout for, must not be {@code null}.
040     * @return The layout for the given repository, never {@code null}.
041     * @throws NoRepositoryLayoutException If the factory cannot create a repository layout for the specified remote
042     *             repository.
043     */
044    RepositoryLayout newInstance(RepositorySystemSession session, RemoteRepository repository)
045            throws NoRepositoryLayoutException;
046
047    /**
048     * The priority of this factory. When multiple factories can handle a given repository, factories with higher
049     * priority are preferred over those with lower priority.
050     *
051     * @return The priority of this factory.
052     */
053    float getPriority();
054}