001package org.eclipse.aether.transport.wagon;
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 org.apache.maven.wagon.Wagon;
023
024/**
025 * A component to acquire and release wagon instances for uploads/downloads.
026 */
027public interface WagonProvider
028{
029
030    /**
031     * Acquires a wagon instance that matches the specified role hint. The role hint is derived from the URI scheme,
032     * e.g. "http" or "file".
033     * 
034     * @param roleHint The role hint to get a wagon for, must not be {@code null}.
035     * @return The requested wagon instance, never {@code null}.
036     * @throws Exception If no wagon could be retrieved for the specified role hint.
037     */
038    Wagon lookup( String roleHint )
039        throws Exception;
040
041    /**
042     * Releases the specified wagon. A wagon provider may either free any resources allocated for the wagon instance or
043     * return the instance back to a pool for future use.
044     * 
045     * @param wagon The wagon to release, may be {@code null}.
046     */
047    void release( Wagon wagon );
048
049}