001package org.eclipse.aether.spi.locator;
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;
023
024/**
025 * A simple infrastructure to programmatically wire the various components of the repository system together when it is
026 * used outside of an IoC container. Once a concrete implementation of a service locator has been setup, clients could
027 * use
028 * 
029 * <pre>
030 * RepositorySystem repoSystem = serviceLocator.getService( RepositorySystem.class );
031 * </pre>
032 * 
033 * to acquire the repository system. Components that implement {@link Service} will be given an opportunity to acquire
034 * further components from the locator, thereby allowing to create the complete object graph of the repository system.
035 *
036 * @deprecated Use some out-of-the-box DI implementation instead.
037 */
038@Deprecated
039public interface ServiceLocator
040{
041
042    /**
043     * Gets an instance of the specified service.
044     * 
045     * @param <T> The service type.
046     * @param type The interface describing the service, must not be {@code null}.
047     * @return The service instance or {@code null} if the service could not be located/initialized.
048     */
049    <T> T getService( Class<T> type );
050
051    /**
052     * Gets all available instances of the specified service.
053     * 
054     * @param <T> The service type.
055     * @param type The interface describing the service, must not be {@code null}.
056     * @return The (read-only) list of available service instances, never {@code null}.
057     */
058    <T> List<T> getServices( Class<T> type );
059
060}