package org.eclipse.aether.spi.locator;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *  http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.util.List;

A simple infrastructure to programmatically wire the various components of the repository system together when it is
used outside of an IoC container. Once a concrete implementation of a service locator has been setup, clients could
use
RepositorySystem repoSystem = serviceLocator.getService( RepositorySystem.class );
 to acquire the repository system. Components that implement Service will be given an opportunity to acquire further components from the locator, thereby allowing to create the complete object graph of the repository system. /**
 * A simple infrastructure to programmatically wire the various components of the repository system together when it is
 * used outside of an IoC container. Once a concrete implementation of a service locator has been setup, clients could
 * use
 * 
 * <pre>
 * RepositorySystem repoSystem = serviceLocator.getService( RepositorySystem.class );
 * </pre>
 * 
 * to acquire the repository system. Components that implement {@link Service} will be given an opportunity to acquire
 * further components from the locator, thereby allowing to create the complete object graph of the repository system.
 */
public interface ServiceLocator
{

    
Gets an instance of the specified service.
Params:
type – The interface describing the service, must not be null.
Type parameters:
<T> – The service type.
Returns:
The service instance or null if the service could not be located/initialized./**
     * Gets an instance of the specified service.
     * 
     * @param <T> The service type.
     * @param type The interface describing the service, must not be {@code null}.
     * @return The service instance or {@code null} if the service could not be located/initialized.
     */
    <T> T getService( Class<T> type );

    
Gets all available instances of the specified service.
Params:
type – The interface describing the service, must not be null.
Type parameters:
<T> – The service type.
Returns:
The (read-only) list of available service instances, never null./**
     * Gets all available instances of the specified service.
     * 
     * @param <T> The service type.
     * @param type The interface describing the service, must not be {@code null}.
     * @return The (read-only) list of available service instances, never {@code null}.
     */
    <T> List<T> getServices( Class<T> type );

}