if (session != null) {
                        configuration.setSystemProperties(session.getSystemProperties());
                        configuration.setUserProperties(session.getUserProperties());
                    } else {
                        configuration.setSystemProperties(getSystemProperties());
                        configuration.setUserProperties(new Properties());

        DefaultProfileActivationContext context = new DefaultProfileActivationContext();
        context.setActiveProfileIds(activatedIds);
        context.setInactiveProfileIds(deactivatedIds);
        context.setSystemProperties(System.getProperties());
        context.setUserProperties(requestProperties);

        final List<ProfileActivationException> errors = new ArrayList<>();

        settingsRequest.setProjectSettingsFile(projectSettingsFile);
        settingsRequest.setUserSettingsFile(userSettingsFile);
        settingsRequest.setSystemProperties(cliRequest.getSystemProperties());
        Properties props = cliRequest.getUserProperties();
        if (cliRequest.getRootDirectory() != null) {
            props = new Properties();

     *
     * @param systemProperties The system properties, may be {@code null}.
     * @return This request, never {@code null}.
     */
    SettingsBuildingRequest setSystemProperties(Properties systemProperties);

    /**
     * Gets the user properties to use for interpolation. The user properties have been configured directly by the user

                .setRemoteRepositories(request.getRemoteRepositories())
                .setPluginArtifactRepositories(request.getPluginArtifactRepositories())
                .setSystemProperties(executionProperties)
                .setUserProperties(new Properties());

        initRepoSession(request, configuration);

        List<MavenProject> projects = new ArrayList<>();

            DefaultRepositorySystemSession rsession = new DefaultRepositorySystemSession(h -> false);
            rsession.setSystemProperties(properties);
            rsession.setConfigProperties(properties);

            ProtoSession session = new ProtoSession(
                    rsession,
                    system,

                // This merge is on purpose because otherwise user properties would override model
                // properties in dependencies the user does not know. See MNG-7563 for details.
                modelRequest.setSystemProperties(
                        toProperties(session.getUserProperties(), session.getSystemProperties()));
                modelRequest.setUserProperties(new Properties());

        finalConfigProperties.putAll(mergedProps);
        finalConfigProperties.putAll(configProps);

        sessionBuilder.setUserProperties(request.getUserProperties());
        sessionBuilder.setSystemProperties(request.getSystemProperties());
        sessionBuilder.setConfigProperties(finalConfigProperties);

        return sessionBuilder;
    }

    private VersionFilter buildVersionFilter(String filterExpression) {

     *
     * @param systemProperties The system properties, may be {@code null}.
     * @return This request, never {@code null}.
     */
    MavenExecutionRequest setSystemProperties(Properties systemProperties);

    /**
     * Gets the system properties to use for interpolation and profile activation. The system properties are collected

     *
     * @param systemProperties The system properties, may be {@code null}.
     * @return This request, never {@code null}.
     */
    ModelBuildingRequest setSystemProperties(Properties systemProperties);

    /**
     * Gets the user properties to use for interpolation and profile activation. The user properties have been