+ 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() : "");
    }

     */
    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 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.

     * Get the default classifier associated to the dependency type.
     * The default classifier can be overridden when specifying
     * the {@link Dependency#getClassifier()}.
     *
     * @return the default classifier, or {@code null}.
     */
    @Nullable
    String getClassifier();

    /**
     * Specifies if the artifact already embeds its own dependencies.
     * This is the case for JEE packages or similar artifacts such as

                artifact.getClassifier(),
                artifact.getBaseVersion());
    }

    private static String getId(ClassRealmConstituent constituent) {
        return getId(
                constituent.getGroupId(),
                constituent.getArtifactId(),
                constituent.getType(),
                constituent.getClassifier(),
                constituent.getVersion());
    }

            Type type = typeRegistry.require(id);
            return new DefaultArtifactHandler(
                    id,
                    type.getExtension(),
                    type.getClassifier(),
                    null,
                    null,
                    type.isIncludesDependencies(),
                    type.getLanguage().id(),

                session,
                artifact.getGroupId(),
                artifact.getArtifactId(),
                artifact.getVersion().toString(),
                artifact.getClassifier(),
                artifact.getExtension(),
                null));
    }

                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());