+ dependency.getType().id() + ":" + dependency.getClassifier();
    }

    private static String getDependencyKey(Dependency dependency) {
        return dependency.getGroupId() + ":" + dependency.getArtifactId() + ":"
                + (dependency.getType() != null ? dependency.getType() : "jar") + ":"
                + (dependency.getClassifier() != null ? dependency.getClassifier() : "");
    }

    }

    // TODO: this is duplicate of PomArtifactHandlerProvider provided one
    static class PomArtifactHandler implements ArtifactHandler {
        @Override
        public String getClassifier() {
            return null;
        }

        @Override
        public String getDirectory() {
            return null;
        }

        @Override
        public String getExtension() {

    String getExtension();

    String getDirectory();

    /**
     * Returns the default classifier used if a different one is not set in pom.xml.
     *
     * @return the classifier
     */
    String getClassifier();

    String getPackaging();

    boolean isIncludesDependencies();

    String getLanguage();

    /**
     * Specifies if the artifact contains java classes and can be added to the classpath.

        this.classifier = classifier;
        this.extension = requireNonNull(extension);
        this.packaging = requireNonNull(packaging);
    }

    @Override
    public String getClassifier() {
        return classifier;
    }

    @Override
    public String getDirectory() {
        return null;
    }

    @Override
    public String getExtension() {
        return extension;

            for (Dependency dependency : project.getDependencies()) {
                String classifier = dependency.getClassifier();
                if (classifier == null) {
                    ArtifactType type = stereotypes.get(dependency.getType());
                    if (type != null) {
                        classifier = type.getClassifier();
                    }
                }
                String key = ArtifactIdUtils.toVersionlessId(

    }

    private File findInProjectLocalRepository(Artifact artifact) {
        // Prefer the consumer POM when resolving POMs from the project-local repository,
        // to avoid treating a build POM as a repository (consumer) POM.
        if ("pom".equals(artifact.getExtension())) {
            String classifier = artifact.getClassifier();

     */
    String getType();

    /**
     * Gets the classifier of the constituent's artifact.
     *
     * @return The classifier or an empty string, never {@code null}.
     */
    String getClassifier();

    /**
     * Gets the version of the constituent's artifact.
     *
     * @return The version, never {@code null}.
     */
    String getVersion();

    /**

    }

    // TODO: this is duplicate of MavenPluginArtifactHandlerProvider provided one
    static class PluginArtifactHandler implements ArtifactHandler {
        @Override
        public String getClassifier() {
            return null;
        }

        @Override
        public String getDirectory() {
            return null;
        }

        @Override
        public String getExtension() {

                session,
                dependency.getGroupId(),
                dependency.getArtifactId(),
                dependency.getVersion(),
                dependency.getClassifier(),
                null,
                dependency.getType()));
    }

    @Nonnull
    default DependencyCoordinates create(@Nonnull Session session, Plugin plugin) {
        // TODO: hard coded string

        path.append(artifact.getArtifactId()).append(ARTIFACT_SEPARATOR).append(artifact.getVersion());

        if (artifact.hasClassifier()) {
            path.append(ARTIFACT_SEPARATOR).append(artifact.getClassifier());
        }

        if (artifactHandler.getExtension() != null
                && !artifactHandler.getExtension().isEmpty()) {
            path.append(GROUP_SEPARATOR).append(artifactHandler.getExtension());