&& Objects.equals(d1.getScope(), d2.getScope())
                && Objects.equals(d1.getSystemPath(), d2.getSystemPath())
                && Objects.equals(d1.getOptional(), d2.getOptional())
                && equals(d1.getExclusions(), d2.getExclusions());
    }

    private boolean equals(Collection<Exclusion> ce1, Collection<Exclusion> ce2) {
        if (ce1.size() == ce2.size()) {

            exclusions.add(convert(exclusion));
        }

        return new Dependency(
                artifact,
                dependency.getScope(),
                dependency.getOptional() != null ? dependency.isOptional() : null,
                exclusions);
    }

    private Exclusion convert(org.apache.maven.model.Exclusion exclusion) {

                String scope = dependency.getScope() != null ? dependency.getScope() : "";
                return session.requireDependencyScope(scope);
            }

            @Override
            public Boolean getOptional() {
                return dependency.isOptional();
            }

            @Nonnull
            @Override
            public Collection<Exclusion> getExclusions() {

                .collect(Collectors.toList());

        return new Dependency(
                artifact,
                dependency.getScope(),
                dependency.getOptional() != null ? dependency.isOptional() : null,
                exclusions);
    }

    private static Exclusion toExclusion(org.apache.maven.model.Exclusion exclusion) {

            if (request.getValidationLevel() >= ModelBuildingRequest.VALIDATION_LEVEL_MAVEN_2_0) {
                validateBoolean(
                        prefix, "optional", problems, errOn30, Version.V20, d.getOptional(), d.getManagementKey(), d);

                if (!management) {
                    validateVersion(

    public boolean isSelectedVersionKnown() throws OverConstrainedVersionException {
        return artifact.isSelectedVersionKnown();
    }

    /** {@inheritDoc} */
    public void setOptional(boolean optional) {
        artifact.setOptional(optional);
    }

    /** {@inheritDoc} */
    public int hashCode() {
        int result = 17;

        result = 37 * result + getGroupId().hashCode();

    void setRelease(boolean release);

    List<ArtifactVersion> getAvailableVersions();

    void setAvailableVersions(List<ArtifactVersion> versions);

    boolean isOptional();

    void setOptional(boolean optional);

    ArtifactVersion getSelectedVersion() throws OverConstrainedVersionException;

    boolean isSelectedVersionKnown() throws OverConstrainedVersionException;

    }

    @Override
    public boolean isSelectedVersionKnown() throws OverConstrainedVersionException {
        return versionRange.isSelectedVersionKnown(this);
    }

    @Override
    public void setOptional(boolean optional) {
        this.optional = optional;
    }