Directory for DBFlute properties

Required (Basic) Properties:
o basicInfoMap.dfprop
o databaseInfoMap.dfprop

Properties for additional information:
o additionalForeignKeyMap.dfprop
o additionalPrimaryKeyMap.dfprop
o additionalUniqueKeyMap.dfprop (manual making)
o additionalTableMap.dfprop (manual making)

Properties for implementation environments:
o classificationDefinitionMap.dfprop
o classificationDeploymentMap.dfprop

    /**
     * Gets the system properties to use for interpolation. The system properties are collected from the runtime
     * environment like {@link System#getProperties()} and environment variables.
     *
     * @return The system properties, never {@code null}.
     */
    Properties getSystemProperties();

    /**

        then:
        formatTree(result) == '''<chapter>
    <section>
        <title>Properties</title>
        <section>
            <title>Properties added by the <literal>thingo</literal> plugin</title>
            <titleabbrev><literal>thingo</literal> plugin</titleabbrev>
            <table>
                <title>Properties - <literal>thingo</literal> plugin</title>
                <thead>
                    <tr>

        return this;
    }

    @Override
    public Properties getSystemProperties() {
        if (systemProperties == null) {
            systemProperties = new Properties();
        }

        return systemProperties;
    }

    @Override
    public DefaultSettingsBuildingRequest setSystemProperties(Properties systemProperties) {
        if (systemProperties != null) {

     * Parses a sequence of XML elements and converts them to the appropriate {@link Properties} type.
     *
     * @param parser The XML parser
     * @return Converted Properties instance
     */
    private static Properties parseProperties(final XmlPullParser parser) throws Exception {
        final Properties properties = newImplementation(parser, Properties.class);
        while (parser.nextTag() == XmlPullParser.START_TAG) {

        Files.writeString(mavenUserProps, "${includes} = ?\"${user.home}/maven.properties\"\n");
        Path userDirectory = fs.getPath("/user");
        Files.createDirectories(userDirectory);
        Path propsPath = userDirectory.resolve("maven.properties");
        Files.writeString(propsPath, "${includes} = default.properties,?env-${env.envName}.properties\n");

                    "type": "object",
                    "properties": {"message": {"title": "Message", "type": "string"}},
                },
                "User": {
                    "title": "User",
                    "required": ["username", "email"],
                    "type": "object",
                    "properties": {
                        "username": {"title": "Username", "type": "string"},

								<path>${project.build.directory}/fess/WEB-INF/classes/fess_config.properties</path>
								<path>${project.build.directory}/fess/WEB-INF/classes/fess_env_crawler.properties</path>
								<path>${project.build.directory}/fess/WEB-INF/classes/fess_env_suggest.properties</path>
								<path>${project.build.directory}/fess/WEB-INF/classes/fess_env_thumbnail.properties</path>

            "schemas": {
                "Item": {
                    "title": "Item",
                    "required": ["name", "price"],
                    "type": "object",
                    "properties": {
                        "name": {"title": "Name", "type": "string"},
                        "description": {
                            "title": "Description",

    @Nonnull
    public static Map<String, String> toMap(Properties properties) {
        requireNonNull(properties, "properties");
        HashMap<String, String> map = new HashMap<>();
        for (String key : properties.stringPropertyNames()) {
            map.put(key, properties.getProperty(key));
        }
        return map;
    }

    @Nonnull
    public static Properties toProperties(Map<String, String> properties) {