// Maven 3.x is always using 4.0.0 version to load the supermodel, so
            // do the same when loading a dependency.  The model validator will also
            // check that field later.
            superModelVersion = "4.0.0";
        }
        ModelData superData = new ModelData(null, getSuperModel(superModelVersion));

        // profile activation

   *
   * <p>The returned navigable set will be serializable if the specified navigable set is
   * serializable.
   *
   * <p><b>Java 8+ users and later:</b> Prefer {@link Collections#unmodifiableNavigableSet}.
   *
   * @param set the navigable set for which an unmodifiable view is to be returned
   * @return an unmodifiable view of the specified navigable set

    @Nullable Object[] alternatingKeysAndValues;
    int size;
    boolean entriesUsed;
    /**
     * If non-null, a duplicate key we found in a previous buildKeepingLast() or buildOrThrow()
     * call. A later buildOrThrow() can simply report this duplicate immediately.
     */
    @Nullable DuplicateKey duplicateKey;

    /**
     * Creates a new builder. The returned builder is equivalent to the builder generated by {@link

        if (pom != null) {
            request.setMultiModuleProjectDirectory(pom.getParentFile());
        }

        return request;
    }

    // layer the creation of a project builder configuration with a request, but this will need to be
    // a Maven subclass because we don't want to couple maven to the project builder which we need to
    // separate.

  }

  /**
   * Computes the difference between two maps. This difference is an immutable snapshot of the state
   * of the maps at the time this method is called. It will never change, even if the maps change at
   * a later time.
   *
   * <p>Since this method uses {@code HashMap} instances internally, the keys of the supplied maps
   * must be well-behaved with respect to {@link Object#equals} and {@link Object#hashCode}.
   *

                }
            }

            Severity errOn30 = getSeverity(request, ModelBuilderRequest.VALIDATION_LEVEL_MAVEN_3_0);

            // The file pom may not contain the modelVersion yet, as it may be set later by the
            // ModelVersionXMLFilter.
            if (m.getModelVersion() != null && !m.getModelVersion().isEmpty()) {
                validateModelVersion(problems, m.getModelVersion(), m, VALID_MODEL_VERSIONS);