FessConfig fessConfig = new FessConfig.SimpleImpl() {
            @Override
            public String getSystemProperty(final String key, final String defaultValue) {
                return systemPropMap.getOrDefault(key, defaultValue);
            }
        };
        ComponentUtil.setFessConfig(fessConfig);
        SystemHelper systemHelper = new SystemHelper() {
            @Override

      if (isNullable(param)) {
        args.add(null);
        continue;
      }
      Object defaultValue = getDummyValue(param.getType());
      if (defaultValue == null) {
        throw new ParameterNotInstantiableException(param);
      }
      args.add(defaultValue);
    }
    return args;
  }

  @CheckForNull
  private <T> T getDummyValue(TypeToken<T> type) {

            }
            return null;
        }

        protected String getProperty(final String key, final String defaultValue) {
            return ComponentUtil.getSystemProperties().getProperty(key, defaultValue);
        }

        protected String getResourcePath(final String path) {
            final File file = ResourceUtil.getResourceAsFileNoException(path);

    @Override
    public Object get(final Object key) {
        return getProperties().get(key);
    }

    @Override
    public String getProperty(final String key, final String defaultValue) {
        return getProperties().getProperty(key, defaultValue);
    }

    @Override
    public String getProperty(final String key) {
        return getProperties().getProperty(key);
    }

    @Override

	Length() (length int64, ok bool)
	DecimalSize() (precision int64, scale int64, ok bool)
	Nullable() (nullable bool, ok bool)
	Unique() (unique bool, ok bool)
	ScanType() reflect.Type
	Comment() (value string, ok bool)
	DefaultValue() (value string, ok bool)
}

type Index interface {
	Table() string
	Name() string
	Columns() []string
	PrimaryKey() (isPrimaryKey bool, ok bool)
	Unique() (unique bool, ok bool)
	Option() string
}

| No | Key | Type | Description | Default Value | Since | Source |
| --- | --- | --- | --- | --- | --- | --- |
#foreach($key in $keys)
| $foreach.count. | `$key.key` | `$key.configurationType` | $key.description | #value( $key.defaultValue ) | $key.since | $key.configurationSource |

}

func registerEnvironment[T env.Parseable](name string, defaultValue T, usage string) {
	envName := strings.Replace(strings.ToUpper(name), "-", "_", -1)
	// Note: we do not rely on istio env package to retrieve configuration. We relies on viper.
	// This is just to make sure the reference doc tool can generate doc with these vars as env variable at istio.io.
	env.Register(envName, defaultValue, usage)
	bindViper(name)
}

    }

    public static String getMessage(final String key, final String defaultValue) {
        final Locale locale = LaRequestUtil.getOptionalRequest().map(HttpServletRequest::getLocale).orElse(Locale.ROOT);
        return ComponentUtil.getMessageManager().findMessage(locale, key).orElse(defaultValue);
    }

    public static boolean hasActionRole(final String role) {
        final String[] roles;

     * PluginParameterExpressionEvaluator</a>.
     * @return the default value
     */
    @Nonnull
    String defaultValue() default "";

    /**
     * is the parameter required?
     * @return <code>true</code> if the Mojo should fail when the parameter cannot be injected
     */
    boolean required() default false;

    /**

    throw new UnsupportedOperationException();
  }

  private <T> T pickInstance(T[] instances, T defaultValue) {
    return pickInstance(Arrays.asList(instances), defaultValue);
  }

  private <T> T pickInstance(Collection<T> instances, T defaultValue) {
    if (instances.isEmpty()) {
      return defaultValue;
    }
    // generateInt() is 1-based.