//
    // 10) Create ProjectDependencyGraph without trimming (as trimming was done in 7). A new topological sort is
    // required after the execution of 9) as the AbstractLifecycleParticipants are free to mutate the MavenProject
    // instances, which may change dependencies which can, in turn, affect the build order.
    //
    // 11) Execute LifecycleStarter.start()
    //
    @SuppressWarnings("checkstyle:methodlength")

    /**
     * Builds a project descriptor from the specified POM file.
     *
     * @param projectFile The POM file to build the project from, must not be {@code null}.
     * @param request The project building request that holds further parameters, must not be {@code null}.
     * @return The result of the project building, never {@code null}.

                            problems,
                            BuilderProblem.Severity.ERROR,
                            "pluginGroups.pluginGroup[" + i + "]",
                            null,
                            "must denote a valid group id and match the pattern " + ID);
                }
            }
        }

        List<Server> servers = settings.getServers();

        if (servers != null) {

     *
     * @param session the {@link Session}, must not be {@code null}
     * @param globalToolchainsSource The {@link Source} pointing to the global toolchains, must not be {@code null}
     * @param userToolchainsSource The {@link Source} pointing to the user toolchains, must not be {@code null}
     * @throws ToolchainsBuilderException if the project cannot be created

     * the returned model and must not rely on the input model being updated.
     *
     * @param model The model to interpolate, must not be {@code null}.
     * @param projectDir The project directory, may be {@code null} if the model does not belong to a local project but
     *            to some artifact's metadata.
     * @param request The model building request that holds further settings, must not be {@code null}.

    }

    /**
     * Validate the specified settings.
     *
     * @param settings The settings to validate, must not be {@code null}.
     * @return The list of problems that were encountered, must not be {@code null}.
     */
    @Nonnull
    default List<BuilderProblem> validate(@Nonnull Settings settings) {
        return validate(settings, false);
    }

     * has a current project, its plugin repositories will be used as well.
     *
     * @param plugin The plugin for which to resolve a version, must not be {@code null}.
     * @param session The Maven session to use, must not be {@code null}.
     */
    public DefaultPluginVersionRequest(Plugin plugin, MavenSession session) {
        setGroupId(plugin.getGroupId());

    /**
     *
     * @param model the model, must not be {@code null}
     * @param logger the logger, must not be {@code null}
     */
    protected DefaultToolchain(ToolchainModel model, Logger logger) {
        this.model = model;
        this.logger = logger;
    }

    /**
     *
     * @param model the model, must not be {@code null}
     * @param type the type

     *
     * @param model The model into which to inject the default plugin executions for its packaging, must not be
     *            <code>null</code>.
     * @param request The model building request that holds further settings, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */

    /**
     * Determines the mirror for the specified repository.
     *
     * @param repository The repository to determine the mirror for, must not be {@code null}.
     * @param mirrors The available mirrors, may be {@code null}.
     * @return The mirror specification for the repository or {@code null} if no mirror matched.
     */