/*
     * @see junit.framework.TestCase#setUp()
     */
    @BeforeEach
    public void setUp() throws Exception {
        conflictResolver = (ConflictResolver) container.lookup(ConflictResolver.ROLE, roleHint);

        a1 = createArtifact("a", "1.0");
        a2 = createArtifact("a", "2.0");
        b1 = createArtifact("b", "1.0");
    }

        <field>
          <name>roles</name>
          <version>3.0.0+</version>
          <description>
            The roles the contributor plays in the project. Each role is described by a
            {@code role} element, the body of which is a role name. This can also be used to
            describe the contribution.
          </description>
          <association>
            <type>String</type>

      <!-- see o.a.m.plugin.descriptor.Requirement -->
      <fields>
        <field>
          <name>role</name>
          <required>true</required>
          <version>1.0.0+</version>
          <type>String</type>
          <description></description>
        </field>
        <field xml.tagName="role-hint">
          <name>roleHint</name>
          <version>1.0.0+</version>
          <type>String</type>

        }
    }

    private <T> Collection<T> getExtensionComponents(Collection<MavenProject> projects, Class<T> role) {
        Collection<T> foundComponents = new LinkedHashSet<>();
        foundComponents.addAll(lookup.lookupList(role));
        foundComponents.addAll(getProjectScopedExtensionComponents(projects, role));
        return foundComponents;
    }

 * formed by a combination of group id, artifact id, version and tag. The first three components generally refer to the
 * identity of a model. The tag allows for further classification of the associated data on the sole discretion of the
 * model builder.
 *
 */
public interface ModelCache {

    <T> T computeIfAbsent(String groupId, String artifactId, String version, String tag, Supplier<T> data);