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.transport;
020
021import org.eclipse.aether.RepositorySystemSession;
022import org.eclipse.aether.repository.RemoteRepository;
023import org.eclipse.aether.transfer.NoTransporterException;
024
025/**
026 * A factory to create transporters. A transporter is responsible for uploads/downloads to/from a remote repository
027 * using a particular transport protocol. When the repository system needs a transporter for a given remote repository,
028 * it iterates the registered factories in descending order of their priority and calls
029 * {@link #newInstance(RepositorySystemSession, RemoteRepository)} on them. The first transporter returned by a factory
030 * will then be used for the transfer.
031 */
032public interface TransporterFactory {
033
034    /**
035     * Tries to create a transporter for the specified remote repository. Typically, a factory will inspect
036     * {@link RemoteRepository#getProtocol()} to determine whether it can handle a repository.
037     *
038     * @param session The repository system session from which to configure the transporter, must not be {@code null}.
039     *            In particular, a transporter should obey the timeouts configured for the session.
040     * @param repository The remote repository to create a transporter for, must not be {@code null}.
041     * @return The transporter for the given repository, never {@code null}.
042     * @throws NoTransporterException If the factory cannot create a transporter for the specified remote repository.
043     */
044    Transporter newInstance(RepositorySystemSession session, RemoteRepository repository) throws NoTransporterException;
045
046    /**
047     * The priority of this factory. When multiple factories can handle a given repository, factories with higher
048     * priority are preferred over those with lower priority.
049     *
050     * @return The priority of this factory.
051     */
052    float getPriority();
053}