@Override
    public Collection<Exclusion> getExclusions() {
        return new MappedCollection<>(dependency.getExclusions(), this::toExclusion);
    }

    private Exclusion toExclusion(org.eclipse.aether.graph.Exclusion exclusion) {
        return new Exclusion() {
            @Nullable
            @Override
            public String getGroupId() {
                return exclusion.getGroupId();
            }

            return addDependency(groupId, artifactId, version, scope, (Exclusion) null);
        }

        public ProjectBuilder addDependency(
                String groupId, String artifactId, String version, String scope, Exclusion exclusion) {
            return addDependency(groupId, artifactId, version, scope, null, exclusion);
        }

        public ProjectBuilder addDependency(

        MavenProject project = session.getCurrentProject();

        Exclusion exclusion = new Exclusion();
        exclusion.setGroupId( "org.apache.maven.its" );
        exclusion.setArtifactId( "a" );

        new ProjectBuilder( project ).addDependency( "org.apache.maven.its", "b", "0.1", Artifact.SCOPE_RUNTIME,
                                                     exclusion );

        Set<Artifact> artifactDependencies =

            Set<String> exclusions = new LinkedHashSet<>();

            for (ClassRealm extensionRealm : extensionRealms) {
                List<String> excludes = exportedArtifacts.get(extensionRealm);

                if (excludes != null) {
                    exclusions.addAll(excludes);
                }

package org.apache.maven.artifact.resolver.filter;

import java.util.List;

import org.apache.maven.artifact.Artifact;

/**
 * Filter to exclude from a list of artifact patterns.
 *
 * TODO I think this is equiv. to exclusion set filter in maven-core
 */
public class ExcludesArtifactFilter extends IncludesArtifactFilter {
    public ExcludesArtifactFilter(List<String> patterns) {
        super(patterns);
    }

                .map(Dependency::getArtifact)
                .filter(d -> "org.apache.maven".equals(d.getGroupId()))
                .filter(d -> !DefaultPluginValidationManager.EXPECTED_PROVIDED_SCOPE_EXCLUSIONS_GA.contains(
                        d.getGroupId() + ":" + d.getArtifactId()))
                .map(Artifact::getVersion)
                .filter(v -> v.startsWith("2."))
                .collect(Collectors.toSet());

                .map(org.eclipse.aether.graph.Dependency::getArtifact)
                .filter(a -> "org.apache.maven".equals(a.getGroupId()))
                .filter(a -> !DefaultPluginValidationManager.EXPECTED_PROVIDED_SCOPE_EXCLUSIONS_GA.contains(
                        a.getGroupId() + ":" + a.getArtifactId()))
                .filter(a -> a.getVersion().startsWith("3."))

        assertEquals(1, ((List<?>) pom.getValue("dependencyManagement/dependencies[1]/exclusions")).size());
        assertEquals(
                "org.apache.maven.its", pom.getValue("dependencyManagement/dependencies[1]/exclusions[1]/groupId"));
        assertEquals(
                "excluded-managed-dep", pom.getValue("dependencyManagement/dependencies[1]/exclusions[1]/artifactId"));

        Dependency dep1 = new Dependency();
        dep1.setGroupId( "test" );
        dep1.setArtifactId( "test-artifact" );
        dep1.setVersion( "1" );
        dep1.setType( "jar" );

        Exclusion exc = new Exclusion();
        exc.setGroupId( "test" );
        exc.setArtifactId( "test-artifact3" );

        dep1.addExclusion( exc );

        Dependency dep2 = new Dependency();
        dep2.setGroupId( "test" );

     *
     * @return the type
     */
    @Nonnull
    Type getType();

    @Nonnull
    DependencyScope getScope();

    @Nullable
    Boolean getOptional();

    @Nonnull
    Collection<Exclusion> getExclusions();