001package org.eclipse.aether.impl;
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.Collection;
023
024import org.eclipse.aether.artifact.Artifact;
025import org.eclipse.aether.metadata.Metadata;
026
027/**
028 * A metadata generator that participates in the installation/deployment of artifacts.
029 * 
030 * @provisional This type is provisional and can be changed, moved or removed without prior notice.
031 */
032public interface MetadataGenerator
033{
034
035    /**
036     * Prepares the generator to transform artifacts.
037     * 
038     * @param artifacts The artifacts to install/deploy, must not be {@code null}.
039     * @return The metadata to process (e.g. merge with existing metadata) before artifact transformations, never
040     *         {@code null}.
041     */
042    Collection<? extends Metadata> prepare( Collection<? extends Artifact> artifacts );
043
044    /**
045     * Enables the metadata generator to transform the specified artifact.
046     * 
047     * @param artifact The artifact to transform, must not be {@code null}.
048     * @return The transformed artifact (or just the input artifact), never {@code null}.
049     */
050    Artifact transformArtifact( Artifact artifact );
051
052    /**
053     * Allows for metadata generation based on the transformed artifacts.
054     * 
055     * @param artifacts The (transformed) artifacts to install/deploy, must not be {@code null}.
056     * @return The additional metadata to process after artifact transformations, never {@code null}.
057     */
058    Collection<? extends Metadata> finish( Collection<? extends Artifact> artifacts );
059
060}