aether-api/src/main/java/org/eclipse/aether/artifact/Artifact.java

/*
 * 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.
 */
package org.eclipse.aether.artifact;

import java.io.File;
import java.util.Map;

/**
 * A specific artifact. In a nutshell, an artifact has identifying coordinates and optionally a file that denotes its
 * data. <em>Note:</em> Artifact instances are supposed to be immutable, e.g. any exposed mutator method returns a new
 * artifact instance and leaves the original instance unchanged. <em>Note:</em> Implementors are strongly advised to
 * inherit from {@link AbstractArtifact} instead of directly implementing this interface.
 * 
 * @noimplement This interface is not intended to be implemented by clients.
 * @noextend This interface is not intended to be extended by clients.
 */
public interface Artifact
{

    /**
     * Gets the group identifier of this artifact, for example "org.apache.maven".
     * 
     * @return The group identifier, never {@code null}.
     */
    String getGroupId();

    /**
     * Gets the artifact identifier of this artifact, for example "maven-model".
     * 
     * @return The artifact identifier, never {@code null}.
     */
    String getArtifactId();

    /**
     * Gets the version of this artifact, for example "1.0-20100529-1213". Note that in case of meta versions like
     * "1.0-SNAPSHOT", the artifact's version depends on the state of the artifact. Artifacts that have been resolved or
     * deployed will usually have the meta version expanded.
     * 
     * @return The version, never {@code null}.
     */
    String getVersion();

    /**
     * Sets the version of the artifact.
     * 
     * @param version The version of this artifact, may be {@code null} or empty.
     * @return The new artifact, never {@code null}.
     */
    Artifact setVersion( String version );

    /**
     * Gets the base version of this artifact, for example "1.0-SNAPSHOT". In contrast to the {@link #getVersion()}, the
     * base version will always refer to the unresolved meta version.
     * 
     * @return The base version, never {@code null}.
     */
    String getBaseVersion();

    /**
     * Determines whether this artifact uses a snapshot version.
     * 
     * @return {@code true} if the artifact is a snapshot, {@code false} otherwise.
     */
    boolean isSnapshot();

    /**
     * Gets the classifier of this artifact, for example "sources".
     * 
     * @return The classifier or an empty string if none, never {@code null}.
     */
    String getClassifier();

    /**
     * Gets the (file) extension of this artifact, for example "jar" or "tar.gz".
     * 
     * @return The file extension (without leading period), never {@code null}.
     */
    String getExtension();

    /**
     * Gets the file of this artifact. Note that only resolved artifacts have a file associated with them. In general,
     * callers must not assume any relationship between an artifact's filename and its coordinates.
     * 
     * @return The file or {@code null} if the artifact isn't resolved.
     */
    File getFile();

    /**
     * Sets the file of the artifact.
     * 
     * @param file The file of the artifact, may be {@code null}
     * @return The new artifact, never {@code null}.
     */
    Artifact setFile( File file );

    /**
     * Gets the specified property.
     * 
     * @param key The name of the property, must not be {@code null}.
     * @param defaultValue The default value to return in case the property is not set, may be {@code null}.
     * @return The requested property value or {@code null} if the property is not set and no default value was
     *         provided.
     * @see ArtifactProperties
     */
    String getProperty( String key, String defaultValue );

    /**
     * Gets the properties of this artifact. Clients may use these properties to associate non-persistent values with an
     * artifact that help later processing when the artifact gets passed around within the application.
     * 
     * @return The (read-only) properties, never {@code null}.
     * @see ArtifactProperties
     */
    Map<String, String> getProperties();

    /**
     * Sets the properties for the artifact. Note that these properties exist merely in memory and are not persisted
     * when the artifact gets installed/deployed to a repository.
     * 
     * @param properties The properties for the artifact, may be {@code null}.
     * @return The new artifact, never {@code null}.
     * @see ArtifactProperties
     */
    Artifact setProperties( Map<String, String> properties );

}